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Another EBL/Fridge Problem


Willum

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Posted

I've been sorting out and upgrading a few bits of our Sprinter based 2003 Frankia i7000 BK.

In the process I'd like to resolve an anomaly (more like horror) I've found on the fridge wiring.

When we bought the motorhome 18 months ago it had recently had the fridge replaced. The original - as far as I can tell - was a RM6705 (AES), the replacement is a RMD8555, again AES. The only explanation given was 'It stopped working' and the new one has all seemed to work OK on all three fuels. It later struck me that we had been shown that the fridge did not operate at all unless you activated a switch on the control panel.

This switch is isolated from power when the control panel 12 volt is turned off. With 20/20 hindsight, I have never owned, nor seen, any other motorhome where the fridge went off if the habitation 12 volt was isolated! Investigation needed. It opened a whole new, family sized, can of worms.

 

Sorry it's a bit of a 'War and Peace' but I've tried to put down as much as I can.

 

Electrics are controlled by a Schaudt EBL 264-9D and the control panel is an IT 264-8.

Amongst many other diagrams and descriptions, I read all of the very good thread started by BruceM regarding his problems with a fridge and an EBL fault and the outcomes. I think I now understand most of how the system works. Yep, my EBL is a different model but the circuit diagrams are remarkably similar. There a couple of bits that my head isn't quite round yet but I'll get to them later.

I've attached the circuit diagram for the EBL 264-9D for reference. Sorry it's poor but 100Kb max is very limiting.

 

What I have found is:

1. 12 volt permanent supply to fridge connected through a switch on the IT control panel - which is isolated when the motorhome 12 volt is turned off (as noted previously).

2. EBL Block 1 pin1 is empty - but I would expect that since it is (and was) an AES fridge?

3. EBL Block 1 pin 2 is empty but is burnt out internally on the plug and shows evidence of having overheated the connection to the EBL PCB. (original fridge heater +ve?)

4. EBL Block 1, pin 3 has a cable labelled D+ and is connected at EBL and fridge end and appears to work correctly. It also has an old Scotch-lock on it near the EBL, probably used to connect some experiment (slightly worrying) but there is no cable in the 'piggyback' part, so it's not functional.

5. Block 1 pin 4 has what appears to have been a heavy (6mm), brown sleeved cable cut off flush with the plug. (original fridge heater -ve?)

6. The high current (6mm) feeds to the fridge heater are now connected directly to the battery, the +ve being fused at 20 amp. I can see that they are the original wires and that they came from Block 1, pins 2&4. It's printed on them.

7. The -ve (ground) from the fridge control system is looped into the -ve of the main 12 volt heater supply, ie the -ve cable at point 6 above.

 

To try and make sure the same problem doesn't occur, I want to try and reason out what has - and is - happening with the wiring. The questions in my mind are:

 

a. Something, somewhere has obviously failed and caused the fridge heater +ve connection at the EBL to overheat - but what?. Dead short on the old fridge heater unit? The fact that the fridge has been replaced points the finger in that direction - but I don't have access to the old one, or whoever did the replacement, to find out why.

b. Why is there only overheating evidence on the EBL Block 1 connector at the +ve terminal (pin 2) and not the -ve (pin 4)? Because it was a poor connection to start with?

c. Making the assumption that the EBL is functioning in every other respect - and it appears to be - is there potential for further or similar damage if the system is left wired as it is? I think I can see that under normal circumstances the 12 volt supply for the fridge heater when the engine is running was effectively from the starter battery/alternator (possibly through the EBL connection E20-3F?) but is now being fed through that EBL connector, then through the EBL charging system to the habitation battery and then directly to the fridge. Is that going to overload the EBL, or another part of the system somewhere?

d. The RMD8555 manual states:

'Power supply to the electronics'

'The connection to the electronics must be permanently provided by a 12 volt DC power supply to be protected by a 2A fuse'

Assuming the original fridge had the same requirements I can't positively identify, from the circuit diagram or the physical front face of the EBL, where that came from. After the new fridge was fitted it's obvious from the wiring and tape/connectors that a supply was found and provided by the aforementioned switch on the IT 264-8 control panel. Not a good idea if you want to leave the motorhome with the habitation electrics off and the fridge on!

e. I'm not 100% on the exact function of the connections on Block 2. Are they IN, OUT, Signal lines, or a combination of all three?

f. An asterisk beside Block 2 pins 1&4 seems to refer to a note lower down which says:

* refrigerator lines have to be wired separately from other cables, to battery terminals

Something lost in translation? I'd love to know EXACTLY what that means.

 

In conclusion, I'm almost certainly going to have to take the EBL out and send it off to A&N for inspection and repair but I would like to know, like BruceM, what other implications there are. If I can get answers to the above, I'll be a lot happier putting a rebuilt EBL back in and I can perhaps remove that switched line for the AES supply and take it from the proper place - wherever that may be.

 

Will

1801317593_EBL264-9CCTDiagram.thumb.jpg.5c7645887a250db1c378d45887cde456.jpg

489238511_SchaudtEBL264-9Dpg11top.jpg.a324ab1e8f4abbf493d0defa5f7f1988.jpg

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Posted

Will,

 

As a guest, I first read your posting on another forum, my opinion was that you conclusion regarding the switched supply to your fridge was correct.

 

1.The 12V control supply to the fridge must be maintained whenever the fridge is required to function. Hence there should not be any external switch in this supply. Unfortunately, I am unable to read you posted EBL 264 diagram but I have a diagram for EBL 269 to compare with, but it seems that there are some differences in pin allocations. In my opinion the fridge control supply should be derived from Block 6, using a suitably rated fuse.

 

2. The fridge 12V element power should come from Block 1 pin 1 (+ve) and pin 4 (-ve). Further there is a note on the diagram, which requires that the fridge power supply to the EBL should be routed directly from the habitation (living area) battery on dedicated cables. This supply enters the EBL at Block 2 pins 1 & 4.

 

3. The diagrams show Block 1 pin 2, for compressor/AES. Pin 2 is for a 3 way fridge. Pin 4 is negative for all types of fridge.

 

4. The D+ input is required by an AES fridge, but not by 3 way, or compressor fridges. The input to the EBL is via Block 2 pin 3. (In general it is not a good idea to connect more than the minimum number of items directly to D+, as it is a tapping from the vehicle alternator field circuit. Overload this cct and the alternator will be reluctant to start generating power.)

 

5. Yes the fridge power -ve should be connected to Block 1 pin 4.

 

6. No comment to offer.

 

7. There does not appear to be a dedicated EBL connection for this -ve. It is not a high current load, so probably OK as is.

 

a. The fridge 12V element is one of the higher 12V loads in MH electrics, perhaps 13A. A dead short on the fridge element should have blown the appropriate fuse. Probably a poor connection at the EBL caused localised heating. ( I have had personal experience of such a problem, relating to the original conversion. I had increased the size of the supply cables, and rearranged bullet connectors. I could tell from the crimping pattern that the failed connector was the only one of 4 not recrimped by me.)

 

b. See above.

 

c. I think that the present arrangement may have a bad effect on habitation battery charging from the alternator. There will be additional small but significant voltage drops due to the fridge current flowing in the cables and split charge relay.

 

d. To avoid switching fridge off with other electrics, I suggest connecting to a spare way on Block 6, or if not available using a piggyback or inline subfuse.

 

e. Block 2. Pin 1 is the designated input for supply the fridge, when the engine is running (from alternator).

Pin 2 is a negative input for reading the habitation battery voltage. Pin 5 is the associated +ve connection. Pin 3 is the D+ signal input point from the base vehicle alternator field circuit. Pin 4 is the fridge power -ve supply, and is intended to keep the fridge element current affecting habitation battery charging capability.

 

f. No that makes sense, if you adopt the principle of removing the fridge element current from other power cables.

 

Without at least a photo of the damage to the EBL, I cannot make any suggestions as to the need for repair.

 

Alan

Posted

Hi Alan.

Many thanks for the reply.

Yep, my apologies for the diagrams. They are awful, I know. Trouble was they needed detail to be much use and at an upload limit of only 100Kb it just doesn't work. I tried a second, cropped version, of the upper part of the diagram showing the most relevant bits. Another fail! I tried .png, .pdf and .jpg but none would produce a decent image at that size. I don't know how to get round it.

With reference to the info you've passed on:

I'm very grateful for the fact that there's a lot to digest and I'll go over it again in the morning and work through it.

I'll also go back to the EBL tomorrow and take another look, especially regarding the connections in to Block 2 from the habitation battery. What you said begins to make sense of it, though.

All grist to the mill and I'll reply as soon as I can with what I find.

Will

Posted

If viewing the diagrams on a computer, just increase the magnification above 100%.

 

I suspect the original fridge was removed and a new one fitted as a result of incompetence by whoever had the job of fault finding. I have had the same experience with the 7 Series Dometic Fridge on my van. The 'technician' at the Dometic trained dealership fitted parts that were fine and nothing to do with my problem. Then I was told that after consulting Dometic Technical HQ that the Fridge was u/s and a new one needed at a cost of over £2,000. I declined, took the van home, cleaned the gas burner, cleaned out the soot from the flue and it has worked fine for the past 2 years.

 

See if you can get a recommendation from someone who actually is capable of fault finding on your fridge and take the van to him. Otherwise you may be going round in circles.

 

I suspect the overheated connection on your EBL was the original fault with the previous fridge (although the fuse should have blown). Any other discrepancy you find may be due to a botched repair attempted job.

Posted
747 - 2020-12-06 11:28 PM

 

If viewing the diagrams on a computer, just increase the magnification above 100%.

 

I suspect the original fridge was removed and a new one fitted as a result of incompetence by whoever had the job of fault finding. I have had the same experience with the 7 Series Dometic Fridge on my van. The 'technician' at the Dometic trained dealership fitted parts that were fine and nothing to do with my problem. Then I was told that after consulting Dometic Technical HQ that the Fridge was u/s and a new one needed at a cost of over £2,000. I declined, took the van home, cleaned the gas burner, cleaned out the soot from the flue and it has worked fine for the past 2 years.

 

See if you can get a recommendation from someone who actually is capable of fault finding on your fridge and take the van to him. Otherwise you may be going round in circles.

 

I suspect the overheated connection on your EBL was the original fault with the previous fridge (although the fuse should have blown). Any other discrepancy you find may be due to a botched repair attempted job.

Hi 747

Yep, I'm prepared to accept that it wasn't necessarily the fridge itself that failed - but unfortunately I've no way of finding out. I've had a similar scenario with a 'technician' making a pigs of sorting out a simple bit of a (fortunately under warranty) Alde system.

I also know what you mean about a sooted up fridge burner and flue. Both our Burstners, A747 and 748 had that problem, we think as a result of 'dirty' LPG.

What is beyond dispute is that the EBL is burnt and I'm now almost certain it's the reason the wiring has been altered. From what Alan said in his post it would seem it's not unknown for a crimp to have been badly made and cause local overheating. Unfortunately the fuse would not necessarily blow in that circumstance but I suppose it would be capable of generating a local hotspot with potentially up to 130 watts drawn on it, in theory up to 240 watts-plus before the 20 amp fuse was even up to its max continuous rating.

Apologies if I didn't make it clear in the OP but the fridge that's in there is working perfectly on all 3 fuels, so I think it's a bit unlikely to point the finger. It's the wiring mess I've discovered that I'm determined to sort out - before it becomes another problem or a repeat problem when we are (hopefully, fingers, toes and everything else crossed) sunning ourselves in warmer climes next winter.

I also think that another 'beyond doubt' bit is that the EBL is going to have to come out and make its way to AandN to get sorted out. I trust them! (bless him, RIP, Allan)

Will

ps which of us is the 'alter ego'? :-D

Posted
747 - 2020-12-06 11:28 PM

 

If viewing the diagrams on a computer, just increase the magnification above 100%...

That's only likely to be effective if the resolution of the original image is good quality, and the higher the original image’s resolution the larger the file size. And the larger the file size the less likely that the image can be kept below these forums’ 100KB limit.

 

I can attach files up to 200KB and if an attached image looks ike it can be ‘improved’ I may decide to do this. But although the two diagrams above (now 154KB and 116KB in size) are sharper and more legible than before, their original resolution prevents them being improved much further and still be attachable to a posting.

 

Obviously, if someone wanted to export either of the diagrams to their own computer and increase their size and play about with their quality, that would be practicable - but if an attempt were then made to put the resultant image back on these forums, the 100KB (or 200KB) limit would still apply and there’s no way round that.

Posted
Derek Uzzell - 2020-12-07 9:06 AM

That's only likely to be effectve if the resolution of the original image is good quality, and the higher the original image’s resolution the larger the file size. And the larger the file size the less likely that the image can be kept below these forums’ 100KB limit.

 

I can attach files up to 200KB and if an attached image looks ike it can be ‘improved’ I may decide to do this. But although the two diagrams above (now 154KB and 116KB in size) are sharper and more legible than before, their original resolution prevents them being improved much further and still be attachable to a posting.

 

Obviously, if someone wanted to export either of the diagrams to their own computer and increase their size and play about with their quality, that would be practicable - but if an attempt were then made to put the resultant image back on these forums, the 100KB (or 200KB) limit would still apply and there’s no way round that.

Yep, it's a bit of a conundrum if you need the detail - which I think this one probably does if there's someone with the knowledge but no diagram available.

The whole document came direct from Schaudt's excellent support system. It has perfectly legible diagrams and is only 422Kb in .pdf format. Page 11 (The wiring diagram) on its own is 169Kb in .pdf, probably because it's the most data-dense part of the book. Page 11 alone in .jpg format is 433Kb (testament to the efficiency of the .pdf format) and Page 11 comes out at 368Kb in .png.

Cropping off bits of diagram in .pdf doesn't help as the file size isn't reduced - at least not according to the Preview Editor App in Mac OS.

Derek: I could email the whole document to you to extract the relevant and upload if it would help the matter and allow folk to see a better image.

What are the chances that the upload allowance could be upped a bit (a lot!)? Most sites are much, much more generous.

Other than that, I'm going out in the cold and frost to pull out an iffy EBL unit - VERY CAREFULLY! 8-)

 

Will

Posted
747Heavy - 2020-12-07 12:47 PM

==============================================================================

==============================================================================

Other than that, I'm going out in the cold and frost to pull out an iffy EBL unit - VERY CAREFULLY! 8-)

 

Will

Will,

 

I would not rush into that labour and expense, unless you are determined on restoration to original status.

 

The damage to the EBL terminal is most likely due to a bad connection at that point. I have calculated that a contact resistance as low as 0.1 Ohm would dissipate about 10 Watts at 12v and 13.5 Watts at 14V. Quite sufficient to cause overheating in the local area, which would make the situation worse.

 

You may wish to consider diverting the fridge element supply to the starter battery and thus avoid the load being routed through the EBL I do recommend moving the control supply point.

 

I note that you queried the term "service battery", This refers to the habitation, or as Schaudt call it the Living Area Battery, (LAB). In this respect I admire the Italians, who on their Camperonline forum almost exclusively use the the abbreviations BM (Battery Motore?), and BS (Service Battery). This is preferable to the misuse of the name Leisure Battery, which is a type of battery, not the application.

 

Alan

Posted
Alanb - 2020-12-07 2:32 PM

 

747Heavy - 2020-12-07 12:47 PM

==============================================================================

==============================================================================

Other than that, I'm going out in the cold and frost to pull out an iffy EBL unit - VERY CAREFULLY! 8-)

 

Will

Will,

 

I would not rush into that labour and expense, unless you are determined on restoration to original status.

 

The damage to the EBL terminal is most likely due to a bad connection at that point. I have calculated that a contact resistance as low as 0.1 Ohm would dissipate about 10 Watts at 12v and 13.5 Watts at 14V. Quite sufficient to cause overheating in the local area, which would make the situation worse.

 

You may wish to consider diverting the fridge element supply to the starter battery and thus avoid the load being routed through the EBL I do recommend moving the control supply point.

 

I note that you queried the term "service battery", This refers to the habitation, or as Schaudt call it the Living Area Battery, (LAB). In this respect I admire the Italians, who on their Camperonline forum almost exclusively use the the abbreviations BM (Battery Motore?), and BS (Service Battery). This is preferable to the misuse of the name Leisure Battery, which is a type of battery, not the application.

 

Alan

Points taken and thanks. Reality and other aspects (not least an emergency appointment with the dentist :-( ) got in the way long before I got anywhere near it today and the EBL is still firmly attached to the floor!

Quite a lot is going to depend on the state of the interior when the lid comes off.

Even before I do pull it and take the lid off to look, I know I'm going to have to source at least a couple of the crimped connectors for it. Even the unused 'ways' are completely empty, so not even one I could liberate from there. Do you perchance know of a source of them, or a designation for the type, maybe even the plastic plug bodies as well?

 

That's also an interesting point regarding the 'Service' battery and 'Leisure' battery. Habitation battery and Engine, Starter, or Prime Mover battery in my dictionary. As you say, a Leisure battery is a type of battery.

I'll go back and reread the bits with that in mind.

 

Will

Posted

It's a "snipped" copy of part the original PDF, but hosted on an external site and linked to in the post (which avoids the 100K limit).

 

It is only 140K at that resolution, but still too big for upload.

Posted
Alanb - 2020-12-07 3:32 PM

In this respect I admire the Italians, who on their Camperonline forum almost exclusively use the the abbreviations BM (Battery Motore?), and BS (Service Battery). This is preferable to the misuse of the name Leisure Battery, which is a type of battery, not the application.

Alan

Being Italian I may confirm.

BM = Batteria Motore = Engine (or start) Battery.

BS = Batteria Servizi = Services Battery (habition, all appliances but engine).

 

Max

Posted
Robinhood - 2020-12-07 3:47 PM

 

It's a "snipped" copy of part the original PDF, but hosted on an external site and linked to in the post (which avoids the 100K limit).

 

It is only 140K at that resolution, but still too big for upload.

Understood. Ta

Will

Posted
mtravel - 2020-12-07 3:53 PM

 

Alanb - 2020-12-07 3:32 PM

In this respect I admire the Italians, who on their Camperonline forum almost exclusively use the the abbreviations BM (Battery Motore?), and BS (Service Battery). This is preferable to the misuse of the name Leisure Battery, which is a type of battery, not the application.

Alan

Being Italian I may confirm.

BM = Batteria Motore = Engine (or start) Battery.

BS = Batteria Servizi = Services Battery (habition, all appliances but engine).

 

Max

Thank you, Max.

Haven't we 'met' before? (lol) (lol) (lol)

 

Will

Posted
747Heavy - 2020-12-07 4:59 PM

 

Thank you, Max.

Haven't we 'met' before? (lol) (lol) (lol)

 

Will

May be either in this forum (NORWAY's topic) or in Chattebox among covid and anti-italian topics... (lol) (lol) (lol)

Posted
Derek Uzzell - 2020-12-07 9:06 AM

 

747 - 2020-12-06 11:28 PM

 

If viewing the diagrams on a computer, just increase the magnification above 100%...

That's only likely to be effective if the resolution of the original image is good quality, and the higher the original image’s resolution the larger the file size. And the larger the file size the less likely that the image can be kept below these forums’ 100KB limit.

 

I can attach files up to 200KB and if an attached image looks ike it can be ‘improved’ I may decide to do this. But although the two diagrams above (now 154KB and 116KB in size) are sharper and more legible than before, their original resolution prevents them being improved much further and still be attachable to a posting.

 

Obviously, if someone wanted to export either of the diagrams to their own computer and increase their size and play about with their quality, that would be practicable - but if an attempt were then made to put the resultant image back on these forums, the 100KB (or 200KB) limit would still apply and there’s no way round that.

Read OK when I upped my magnification on the netbook. I am not intending to give any advice on the problem as I would prefer to see the whole picture up close. But I will comment on the fact that Block 1 is not wired to spec. And the fact that 12 volt power is lost when the 12 volt is isolated at the control panel. This would suggest that the 12 volt supply to the fridge has been rerouted because of the burnt connection at the correct position. This should narrow down the problem. Apart from one burnt pin connection, I don't think there is anything wrong with the EBL.

 

Good luck with it anyway

 

I have a bit of amateurish DIY on my van (adding more DIN sockets). It results in a voltage drop to the sockets but I have left it as it is better than a full 14.4 volts when using or charging small appliances. I added an appropriate fuse to the supply and will just leave it as it is.

Posted

Will,

Just to add to the other comments -

 

Although your EBL has separate outputs for absorption and compressor type fridges, these outputs will be identical if you remove the internal 20A fuse. In fact, later Schaudt EBLs only have one fridge relay and add a note to remove the fuse as required.

 

It would seem that rather than fixing the burnt out connector, they simply rewired the fridge directly to the starter battery (via a fuse). You must also keep the connection from Block 2 pin 1 (batt1 for refrigerator) as this also provides a charge current for your starter battery while on EHU. It is also used to display the starter battery voltage on the display panel (if available). The fuse rating could be reduced to 5A as it no longer feeds the fridge. You will also lose the ability to run the fridge from excess solar power but unless you have a huge solar setup, this is no great loss in my opinion.

 

To prevent the fridge heater draining the starter battery while the engine is off, some fridges (including your RMD8555) have a D+ input to cut off power when the engine is not running. This duplicates the function of the fridge relays inside your EBL. This D+ MUST be connected with your permanent fridge connection to the started battery.

 

The (universal) Mate-n-lock connectors are rated at 19A (with 6 sqmm wires and with only 2 contacts carrying this current). This will give a 30degC temperature rise above ambient so will be quite warm to the touch. The problem with this type of connector is that they rely on the the spring retention force between the pin and socket to maintain a good connection. This spring force can weaken over time due to temperature cycling, vibration and how many times they have been plugged/unplugged. As the retention force weakens, the contact resistance goes up a bit meaning they get slightly hotter which makes the problem worse. Over many cycles at high current, it is not uncommon for the contact to overheat and fail in a similar way to as you describe.

 

To reduce the effects of normal vibrations you get while driving, you should try to secure the cable harness as close to the EBL as possible to minimize any movement. Also don't plug/unplug any more than is necessary (the manufacturer specifies a maximum of 50 times).

 

If you intend to repair the EBL, I would strongly recommend that you also change the harness connector if it shows any signs of overheating. This could result in a misalignment of the contacts. These can be a pain to remove without the correct extraction tool but I made one up using a telescopic aerial from an old portable radio. Just cut off the end with the largest diameter and the internal sections can be pushed out. Select one of the sections that just fits over the pin and compresses the barbs that hold the contact in the housing.

 

Make sure you get the correct crimp for the wire size you intend to use. The larger ones are also available in phosphor bronze (rather than made of brass) with either a tin or gold finish. Ideally, this finish should match the other part of the connector. The phosphor bronze generally has better spring retention. I bought crimps from Farnell but for small quantities, ebay may be better. The part numbers for the crimps that I have (tin plated, phos. bronze for 10awg wire) are -

350923-3 or 640310-3 for the pin and 350922-3 or 640309-3 for the socket. The 350... numbers are supplied on a strip and the 640... are loose.

 

There are several reasons for "* refrigerator lines have to be wired separately from other cables, to battery terminals".

1) As mentioned above, these wires also supply the EHU charge current to the starter battery. You do not want to interrupt this through a relay or switch etc.

2) The fridge draws over 10amps so would reduce the voltage to charge the habitation battery (if it were using the same wire)

3) The wire is also used to monitor the starter battery voltage so you do not want any significant voltage drop. When the engine is off, the fridge element will be off too so no significant voltage drop.

 

I agree that it would be better to rewire the fridge control power (obviously not its heater element) so itis always on. My Frankia with a Schaudt EBL (more recent model), has two off states. One which switches off most of the lights etc. but leaves essential items still on (fridge, one set of lights etc.) and another mode (long term storage) that switches everything off. I guess the earlier EBLs had only the one off state. In my Frankia manual, it describes what the various EBL outputs feed. You probably need to move the fridge control feed onto circuit 4 or 5 on block 6 (with a suitable size fuse)

Posted
747Heavy - 2020-12-07 3:39 PM

 

===================================================================================

 

Even before I do pull it and take the lid off to look, I know I'm going to have to source at least a couple of the crimped connectors for it. Even the unused 'ways' are completely empty, so not even one I could liberate from there. Do you perchance know of a source of them, or a designation for the type, maybe even the plastic plug bodies as well?

 

===================================================================================

Will

Mate'n Lock (Lok?) connectors. Link to male pins here.

 

Alternatively you could try RS Components, or Farnells.

 

Alan

Posted

Will,

 

Just a thought. If your EBL Block 1 housing has been damaged, you may be thinking about changing it. The connectors are available as a complete kit.

 

An extractor tool is a usefull accessory. I havn't found a specific online source, but there are some cheap kits on Ebay, which would probably suffice. I made my own extractor for Mate'n Lock, by boring out a nail of appropriate diameter. The operation requires a bench drill press.

 

Alan

Posted
Alanb - 2020-12-07 6:46 PM

 

747Heavy - 2020-12-07 3:39 PM

 

===================================================================================

 

Even before I do pull it and take the lid off to look, I know I'm going to have to source at least a couple of the crimped connectors for it. Even the unused 'ways' are completely empty, so not even one I could liberate from there. Do you perchance know of a source of them, or a designation for the type, maybe even the plastic plug bodies as well?

 

===================================================================================

Will

Mate'n Lock (Lok?) connectors. Link to male pins here.

 

Alternatively you could try RS Components, or Farnells.

 

Alan

 

Alan,

I am not sure if those are the correct pins. There are many different types of connector under the "Mate-N-Lok" description. I am fairly certain the EBL uses "Universal mate-N-Lok" (at least my Schaudt EBL223 does). The connector you linked to is a ".140 Mate-N-Lok" that have different part numbers than the "universal" crimps. I don't know if these crimps are compatible.

 

I might have got the part numbers for the pins and sockets swapped in my previous post. Search Ebay using the 640309-3 & 640310-3 numbers.

 

Here is the summary chart from the Tyco catalogue.

 

mate-n-lok.JPG.591fccb51f38afef5e698c672465f723.JPG

.14MNL.PNG.fe3654ad4dd5a9d2c6affc0974a52915.PNG

univMNL.PNG.30c64b9fd8b4a6b46eab244e94522fa0.PNG

Posted

Hi All

Some excellent information and thanks. A lot to digest.

I've been trawling through RS/Farnell/CPC/eBay and identifying the correct plug and pins isn't exactly easy. Neither is buying less than 5. However, at 30p each, not too bad.

I quick call to one of them to establish the exact pin fitting seems in order.

If I go for a 5 set of plugs and sockets, I can use the spares to remake the mess left inside the back of the fridge housing. It's not dangerous, just a mess, with about 2 metres of spare power cable rolled up with in a tie wrap and scruffy connector crimps.

Luckily I already have the proper crimp tool for the pins.

Any particular thoughts on soldering the crimp as well? Too much risk of stiffening the cable/vibration fracture?

Will

Posted

I think I'm beginning to learn how it 'should' work. I lean towards the 'belt, braces and a couple of tie wraps - just in case' approach.

However, as a crosscheck:

 

plwsm2000 - 2020-12-07 5:28 PM

Will,

Just to add to the other comments -

.............................

It would seem that rather than fixing the burnt out connector, they simply rewired the fridge directly to the starter battery (via a fuse).

Did you mean to say the fridge heater is now wired form the Starter battery - or the Habitation battery? It is currently (no pun intended) wired/fused directly from the habitation battery and not through the EBL. Only the D+ remains connected to Block 1.

 

plwsm2000 - 2020-12-07 5:28 PM

You must also keep the connection from Block 2 pin 1 (batt1 for refrigerator) as this also provides a charge current for your starter battery while on EHU. It is also used to display the starter battery voltage on the display panel (if available). The fuse rating could be reduced to 5A as it no longer feeds the fridge.

I'd discovered that when sorting out a new solar charger. The old LR1218 (now for sale ;-) ) fed in through that point as well.

 

plwsm2000 - 2020-12-07 5:28 PM

You will also lose the ability to run the fridge from excess solar power but unless you have a huge solar setup, this is no great loss in my opinion.

I have 320 watts on the roof but I too doubt it will prove to be capable on very many occasions. Although it often puts the 'AES available' light on, by all accounts even the best of the AES trigger systems have a habit of draining the battery a bit too much before switching back to gas/EHU again. I've wired the line to the fridge but fitted a switch to control it. We do spend long periods 'off-grid' and stationary sometimes, so it may help save the gas. I'm 'in there' sorting this mess out and it's only the cost of a bit of wire and a switch.

 

plwsm2000 - 2020-12-07 5:28 PM

If you intend to repair the EBL, I would strongly recommend that you also change the harness connector if it shows any signs of overheating. This could result in a misalignment of the contacts. These can be a pain to remove without the correct extraction tool but I made one up using a telescopic aerial from an old portable radio. Just cut off the end with the largest diameter and the internal sections can be pushed out. Select one of the sections that just fits over the pin and compresses the barbs that hold the contact in the housing.

It's actually burnt the connector beyond refitting any crimp, so I most certainly will replace it. I bought a reasonable set of removal tools for another job so know what you mean. Right tools = easy. Wrong (butchery) tools = knackered connector.

I've asked elsewhere in this thread but what are your thoughts on solder on the crimps as well? Too much danger of stiffening the cable upstream of the crimp and inviting a vibration fracture?

 

plwsm2000 - 2020-12-07 5:28 PM

Make sure you get the correct crimp for the wire size you intend to use. The larger ones are also available in phosphor bronze (rather than made of brass) with either a tin or gold finish. Ideally, this finish should match the other part of the connector. The phosphor bronze generally has better spring retention. I bought crimps from Farnell but for small quantities, ebay may be better. The part numbers for the crimps that I have (tin plated, phos. bronze for 10awg wire) are -

350923-3 or 640310-3 for the pin and 350922-3 or 640309-3 for the socket. The 350... numbers are supplied on a strip and the 640... are loose.

This is the tricky bit but I'll measure mine and ring CPC technical. They've been good in the past. I do have good crimping tools.

 

plwsm2000 - 2020-12-07 5:28 PM

There are several reasons for "* refrigerator lines have to be wired separately from other cables, to battery terminals".

1) As mentioned above, these wires also supply the EHU charge current to the starter battery. You do not want to interrupt this through a relay or switch etc.

2) The fridge draws over 10amps so would reduce the voltage to charge the habitation battery (if it were using the same wire)

3) The wire is also used to monitor the starter battery voltage so you do not want any significant voltage drop. When the engine is off, the fridge element will be off too so no significant voltage drop.

I assume the provision of a double/heavy enough cable run will have been down to the original constructor but I'll check to see what's there. I'm guessing, being a Frankia, it wasn't skimped. From the start I could see that the original link from EBL Block 1 to the fridge is 6mm. The provision of the D+ sensing system within the fridge AES is going to help, as well.

 

plwsm2000 - 2020-12-07 5:28 PM

..........My Frankia with a Schaudt EBL (more recent model), has two off states. One which switches off most of the lights etc. but leaves essential items still on (fridge, one set of lights etc.) and another mode (long term storage) that switches everything off. I guess the earlier EBLs had only the one off state. In my Frankia manual, it describes what the various EBL outputs feed. You probably need to move the fridge control feed onto circuit 4 or 5 on block 6 (with a suitable size fuse)

In reference to the two 'OFF' states: No such luxury. Much too old - but I can live with that. :-D I'm very protective of my batteries, so take careful notice of what's going on. A previous motorhome (Burstner) had EBL provision for a separate fused link for the AES supply, this obviously doesn't. That said, some muppet had piggybacked an engine block heating pump from the Aldi system off it and upped the fuse value to compensate. The pump failed, blew the fuse and took the fridge with it. The much increased fuse value had surely made it useless as a protection for the AES - which later failed.

 

The big picture is becoming clearer, thanks to the help I've now got. There are other bits I need to reply to in other folk's responses, so I'm not ignoring anyone but I need to get it out and look first.

 

Will

Posted
747Heavy - 2020-12-08 10:51 AM

 

I think I'm beginning to learn how it 'should' work. I lean towards the 'belt, braces and a couple of tie wraps - just in case' approach.

However, as a crosscheck:

 

plwsm2000 - 2020-12-07 5:28 PM

Will,

Just to add to the other comments -

.............................

It would seem that rather than fixing the burnt out connector, they simply rewired the fridge directly to the starter battery (via a fuse).

Did you mean to say the fridge heater is now wired form the Starter battery - or the Habitation battery? It is currently (no pun intended) wired/fused directly from the habitation battery and not through the EBL. Only the D+ remains connected to Block 1.

The fridge heater is normally powered from the starter battery (i.e.alternator) but only when the engine is running (controlled from D+). When the engine is stopped, it must be disconnected from the starter battery to avoid discharging it in just a few hours. This function was performed by the EBL relay that you have now bypassed.

For compressor fridges (and an absoption fridge if you want to use excess solar), these get reconnected to the habitation battery when the engine is stopped. As the heater on the absoption fridge takes over 10 amps continuously, it will soon discharge even a large battery bank - hence the reason for the solar controller output signal to switch on the fridge heater when there is excess solar available.

 

The fridge control circuit is always permanently connected to the habitation battery as it is quite a low current. This just powers the electronics for the switches, LEDs etc.(not the fridge heater element).

 

747Heavy - 2020-12-08 10:51 AM

 

plwsm2000 - 2020-12-07 5:28 PM

You must also keep the connection from Block 2 pin 1 (batt1 for refrigerator) as this also provides a charge current for your starter battery while on EHU. It is also used to display the starter battery voltage on the display panel (if available). The fuse rating could be reduced to 5A as it no longer feeds the fridge.

I'd discovered that when sorting out a new solar charger. The old LR1218 (now for sale ;-) ) fed in through that point as well.

 

plwsm2000 - 2020-12-07 5:28 PM

You will also lose the ability to run the fridge from excess solar power but unless you have a huge solar setup, this is no great loss in my opinion.

I have 320 watts on the roof but I too doubt it will prove to be capable on very many occasions. Although it often puts the 'AES available' light on, by all accounts even the best of the AES trigger systems have a habit of draining the battery a bit too much before switching back to gas/EHU again. I've wired the line to the fridge but fitted a switch to control it. We do spend long periods 'off-grid' and stationary sometimes, so it may help save the gas. I'm 'in there' sorting this mess out and it's only the cost of a bit of wire and a switch.

Your fridge also has a S+ control input that works in a similar way to the D+ control signal. But as I said before, the fridge heater must then be connected to the hab. battery for this to do anything. You should not use this feature if the fridge heater has been permanently wired to the starter battery as it would be quickly discharged as the solar controller only gives the starter battery a trickle charge.

 

747Heavy - 2020-12-08 10:51 AM

 

plwsm2000 - 2020-12-07 5:28 PM

If you intend to repair the EBL, I would strongly recommend that you also change the harness connector if it shows any signs of overheating. This could result in a misalignment of the contacts. These can be a pain to remove without the correct extraction tool but I made one up using a telescopic aerial from an old portable radio. Just cut off the end with the largest diameter and the internal sections can be pushed out. Select one of the sections that just fits over the pin and compresses the barbs that hold the contact in the housing.

It's actually burnt the connector beyond refitting any crimp, so I most certainly will replace it. I bought a reasonable set of removal tools for another job so know what you mean. Right tools = easy. Wrong (butchery) tools = knackered connector.

I've asked elsewhere in this thread but what are your thoughts on solder on the crimps as well? Too much danger of stiffening the cable upstream of the crimp and inviting a vibration fracture?

If you have the correct crimp tool, then it is always best to use this and not to use any solder. Due to capilliary action, the solder tends to wick up the individual strands of wire and makes the connection likely to break under vibration. The only time I would consider doing this is if you can secure the wire a few centimeters from the solder joint so that the actual joint doesn't move. The other problem with soldering a crimp is that the heat from the solder iron can reduce the spring retention force on the contact.

I would add that the manufacturers recommended crimp tool and matching die for this crimp is quite expensive (around £300). If you don't have the recommended tool, you might want to do a crude pull test using some luggage scales on a sample crimp that you have made up. With the correct tool on a 10awg wire, the minimum tensile force is stated to be 311 N (70 lbs).

 

747Heavy - 2020-12-08 10:51 AM

plwsm2000 - 2020-12-07 5:28 PM

Make sure you get the correct crimp for the wire size you intend to use. The larger ones are also available in phosphor bronze (rather than made of brass) with either a tin or gold finish. Ideally, this finish should match the other part of the connector. The phosphor bronze generally has better spring retention. I bought crimps from Farnell but for small quantities, ebay may be better. The part numbers for the crimps that I have (tin plated, phos. bronze for 10awg wire) are -

350923-3 or 640310-3 for the pin and 350922-3 or 640309-3 for the socket. The 350... numbers are supplied on a strip and the 640... are loose.

This is the tricky bit but I'll measure mine and ring CPC technical. They've been good in the past. I do have good crimping tools.

 

plwsm2000 - 2020-12-07 5:28 PM

There are several reasons for "* refrigerator lines have to be wired separately from other cables, to battery terminals".

1) As mentioned above, these wires also supply the EHU charge current to the starter battery. You do not want to interrupt this through a relay or switch etc.

2) The fridge draws over 10amps so would reduce the voltage to charge the habitation battery (if it were using the same wire)

3) The wire is also used to monitor the starter battery voltage so you do not want any significant voltage drop. When the engine is off, the fridge element will be off too so no significant voltage drop.

I assume the provision of a double/heavy enough cable run will have been down to the original constructor but I'll check to see what's there. I'm guessing, being a Frankia, it wasn't skimped. From the start I could see that the original link from EBL Block 1 to the fridge is 6mm. The provision of the D+ sensing system within the fridge AES is going to help, as well.

On my Frankia, they run two 10sqmm wires from the starter battery to the back of the EBL to reduce the voltage drop. I since added a Schaudt B2B so this is not so critical. Frankia also seem to label every wire end to end (in German) including its length which helps with tracing wires.

 

747Heavy - 2020-12-08 10:51 AM

 

plwsm2000 - 2020-12-07 5:28 PM

..........My Frankia with a Schaudt EBL (more recent model), has two off states. One which switches off most of the lights etc. but leaves essential items still on (fridge, one set of lights etc.) and another mode (long term storage) that switches everything off. I guess the earlier EBLs had only the one off state. In my Frankia manual, it describes what the various EBL outputs feed. You probably need to move the fridge control feed onto circuit 4 or 5 on block 6 (with a suitable size fuse)

In reference to the two 'OFF' states: No such luxury. Much too old - but I can live with that. :-D I'm very protective of my batteries, so take careful notice of what's going on. A previous motorhome (Burstner) had EBL provision for a separate fused link for the AES supply, this obviously doesn't. That said, some muppet had piggybacked an engine block heating pump from the Aldi system off it and upped the fuse value to compensate. The pump failed, blew the fuse and took the fridge with it. The much increased fuse value had surely made it useless as a protection for the AES - which later failed.

 

The big picture is becoming clearer, thanks to the help I've now got. There are other bits I need to reply to in other folk's responses, so I'm not ignoring anyone but I need to get it out and look first.

 

Will

Posted
747Heavy - 2020-12-08 10:51 AM

 

I think I'm beginning to learn how it 'should' work. I lean towards the 'belt, braces and a couple of tie wraps - just in case' approach.

However, as a crosscheck:

 

plwsm2000 - 2020-12-07 5:28 PM

Will,

Just to add to the other comments -

.............................

It would seem that rather than fixing the burnt out connector, they simply rewired the fridge directly to the starter battery (via a fuse). ..................................................

...............

Will

plwsm2000:

 

I think - possibly because some of my answers/questions weren't clear enough - we ended up at cross purposes. If my goof, apologies *-)

Either way, I'm getting to the bottom if it thanks to the very good information and advice given by all.

I've eventually tracked down all the bits I need to repair the harness and tidy up the mess behind the fridge as well. Not being willing to pay £1+ for a single crimp from some suppliers and not really wanting 100 of some of the items, it wasn't very straightforward.

Total bill for components, including a new header in the PCB (if needed): a shade under £26 and that includes the wiring parts in the back of the fridge housing.

 

All other comments duly noted, in particular your notes on solder and crimp security. Measuring the pull out force is going to be an interesting exercise. 70lbs is quite a lot, so it's out with the luggage scales, sea fishing line and the engine hoist.

I'll report progress.

 

Will

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