Stecca regulators

[spospe]

I have tried to search for this item, but the search facility of the Forum is not working as I type, so apologies if it has been covered before .......

 

I have just had a 10 amp Stecca solar panel regulator and solar panel fitted to my Duetto (based on the MK7 Transit).

 

According to the Stecca installation booklet it should retain charge details until reset, i.e. it should show the total number of A/H delivered to the leisure battery since it was fitted. What I have found is that the display seems to reset itself to zero every time the vehicle engine is started. For example, yesterday it was showing 14 A/H delivered to the battery, I did a run of about 60 miles and the display then read zero.

 

My question is, is this normal (?)

[spospe]

No comments to date seems to indicate either that my problem is not normal, or that Forum members with Stecca regulators are unaware of the problem, or that I have a faulty unit.

 

I have done some testing and can now say that the effect only occurs at night i.e. when the solar panel is not producing an output.

 

During the day the Stecca maintains the cumulative total figure of A/H put into the leisure battery, but when running at night this figure is reset to zero (as if the regulator had just been installed or reset).

 

Any comments (?)

[spospe]

Update:

 

After a 5000 mile trip round Norway and other shorter UK based journeys it seems that the Stecca "loses" its record of accumulated ampere-hours more-or-less every time that the engine is run. This seems to indicate that there is something about the alternator output that the regulator does not like.

 

I have spoken to one of the firms that install these devices and they say that such behaviour is quite common. In fact, they say that it is quite common for the Stecca regulator to get stuck in a fault condition that can only be cleared by disconnecting it from both battery and solar panel. They were unable to offer any solution, other than fitting switches to allow for ease of re-setting.

 

Stecca state that their regulators are only intended to control solar panels when they are the sole source of power and that they are not intended for use with other power supplies, such as a mains charger or vehicle alternator.

 

I am curious to know if other forum members have experienced these problems and if so how have they been overcome?

 

 

[spospe]

I have now found the cause of the problem and fixed it.

 

Very simply, the dealer who supplied the Duetto and fitted the panel had connected it to the van’s power supply incorrectly. Instead of connecting the panel directly to the habitation battery, they wired it via the van’s control panel in such a way that when the ignition was switched on, the battery was disconnected from the solar panel. It was this disconnecting of the battery (which the Steca uses as a reference to switch itself between 12 and 24 volt working) that caused the problem.

 

Steca specifically state in their installation instructions, that the battery must be connected before the solar panel and when disconnecting, the solar panel must be disconnected before the battery.

 

Due to the way the dealer had wired the battery connection the Steca regulator was using the solar panel output as its reference and presumably setting itself to 24 volt working (it often showed a low battery voltage alarm).

 

So if you are going to install one of these regulators, connect it directly to the habitation battery (via a fuse) and not via any form of switch or relay.

 

Michael