inverter problem

[Idle boater]

We bought our boat 18 months ago and as we knew our mooring had no land line power we had a Sterling 1800w inverter fitted, we used the boat on and off since then without any problems, using the inverter daily for about 6 to 8 hours to power our tv, sky box charge phones/lap top etc.Not having been able to get to the boat for about a month we paid a quick visit yesterday, to check everything was ok, pump out bilge, switch off fridge for winter etc. Engine started ok, batteries were stood at 14.4 (solar panels working fine) no leeks etc, in fact everything seemed A ok, so with engine running we switched on the inverter so we could watch tv for a wee while, and it was just fine for about 30 mins then the power went of for a couple of seconds, this occered 5 or 6 times in the following couple of hours with the lenth of cut getting longer each time, till finally it was off for about 60 seconds before it came back on.

I checked the troubleshooting bit in the brochure but as far as i can see there are no warning lights on the model we have, just a green light which remained on constantly.

 

Your thoughts would be appreciated, Thanks, Mike.

[Arthur Brown]

The solar assisted battery voltage means only that the solar panels are working. They could be charging a low battery or holding a full battery. If you've used the inverter to drive the TV before successfully then I'd look at the rested battery voltage -at least an hour without current in or out of the battery.

[by'eck]

If it was just a case that after charging the domestic batteries the inverter drained them to the point of it dropping out, I would say that battery capacity has dropped to a level that dictates replacement. However you say this occurred with increasing frequency whilst the engine was running.

 

I would check that the domestic batteries are receiving charge current from the engine alternator. If not and there is a fault, the symptoms you describe could be attributed to the batteries recovering slightly after inverter drops out, but with their state-of-charge in a downward spiral. The solar assistance would just prolong this situation but not be sufficient to cure it.

 

It could be that you now have aforementioned U/S batteries as well as engine charging to sort out.

[bottle]

I will take a wild guess, you have not been charging your batteries enough and they are knackered.

 

The voltage reading you took, with the panels working, was the panel voltage not the batteries voltage so will not indicate the state of charge of the batteries

 

 

so with engine running we switched on the inverter so we could watch tv for a wee while, and it was just fine for about 30 mins then the power went of for a couple of seconds, this occered 5 or 6 times in the following couple of hours with the lenth of cut getting longer each time, till finally it was off for about 60 seconds before it came back on.

 

This implies, to me, the batteries are 'flat' and the alternator is working flat out (amps) but the voltage is being held down to below the cut-out voltage of the inverter.

 

Checks will need to be made on the true state of the batteries and also that the alternator is working.

[Chalky]

Most likely the batteries however also check the inverter cooling vents are clear, that the fan/s work ok and that the inverter can get cool air. It could be that the inverter is overheating and shutting down to protect itself - would explain some of the cyclic nature.

[OldGoat]

Could it be that you've left the inverter in standby? Most / many consume 1/2 amp when not in use - that could be 360 amp hours per month.

I have a separate isolator on mine which I switch off when it's not in use.

 

You still need to evaluate if your batteries are knackered or not, then think of a way to disconnect the inverter.

 

 

[by'eck]

Could it be that you've left the inverter in standby? Most / many consume 1/2 amp when not in use - that could be 360 amp hours per month.

I have a separate isolator on mine which I switch off when it's not in use.

 

You still need to evaluate if your batteries are knackered or not, then think of a way to disconnect the inverter.

 

 

 

Actually that's a very good point. I have a Sterling 3.2kW Combi. When the inverter is in power save mode it cycles on and off quite regularly with only a bedside clock and microwave on standby as the AC load - just not quite enough to force the load sensor to keep the inverter running continuously.

 

Unfortunately the OP's 1800 watt Sterling inverter doesn't have this power saver/standby mode.

[Idle boater]

Thanks for your input gents, i will certainly check the vents etc. and run the engine for a good while to chage the betteries, as said there is no stand-by facility on the inverter. I had a full engine service about 8 weeks ago including checking the batteries, and everthing we ok then, plus the alternator which is only 12 months old was charging fine.

 

Thanks. Mike

[bottle]

 

including checking the batteries

 

but what did that involve?

[Chalky]

, plus the alternator which is only 12 months old was charging fine.

 

 

Check the belt for tension. It could be that it's slipping and you're not getting the charge that your expecting

[Guest]

My boat is fitted with a split charge relay that senses the start battery voltage, and the alternator will default to that should it sense a dangerously low voltage, temprorarily disconnecting charge from the domestic bank. This has caused my inverter to drop out on a couple of occasions when the domestic bank is low, and there is a fair load on the inverter. Just a thought.

[jonathanA]

so if its a relatively new sterling (less than 18 months according to the OP's post) then it does have a standby option via a switch on the unit allowing control via the remote control. i.e off (properly off) on or remote (switched on/off by remote control so taking some very small standby current). I can't see how any of the symptoms described by the OP could be a result of low battery voltage/insufficent charging as the inverter would bleep if the battery voltage was too low and stop working until power cycled (at least thats what all the inverters I've seen do).

 

this sounds more like the overheating issue mentioned earlier or a fault with the internal doings.

 

Edited for clarity

Edited September 20, 2013 by jonathanA

[Idle boater]

Further update, Still concerned we managed a night onboard, i ran the engine for about 3 hrs, regulator still showed 14 plus in batts (sunny day) penels working ok. we had inverter on all the time engine was running with no probs, turned engine off and left inverter on, running tv and sky box for a further 4 or 5 hrs wthout ant problems, mmmmmmmmmmmmmmmm puzzling indeed, maybe it was the batteries ??

[WotEver]

... maybe it was the batteries ??

 

Or an intermittent inverter fault - perhaps damp which has now dried out?

 

Tony