Onan generator, prosine 2.0 inverter/charger, & Starcool

AEJ · 04-23-2009, 09:35 AM

Perhaps someone on the forum can provide some guidance regarding a problem I'm having running my Starcool AC from Onan genset w/ prosine inverter. I have an email into Peter at SMBW that I hope will yield a solution that doesn't require me to seek proffesional rv service. Here is the symtoms( content of email to SMBW):

I am trying to figure out why I can't get my prosine 2.0 inverter to recognize AC in from generator when I try to start the Starcool airconditioning. After the Onan generator(gas) has been running about 5 minutes and is recognized by the inverter/charger and is charging the house battery, I start the fans for the starcool and everything is still good as far as the inverter and the input AC from the generator. When I switch the thermostat switch to cool to start the starcool the inverter immediately doen't recognize the generator electricity as good enough, although you very briefly will see that the inverter senses the ac in but immediately rejects it and never will let the charger charge. This also shows as AC Bad for two reasons: Low Cycle V IN or Low Average V In. When I do this I hear the generator surge just slightly. Is there anything I can do to solve this?
Any help would be appreciated.

I have already set the prosine specs to accept the lowest Voltage & hertz that it allows for AC current .

Any suggestions as to how I might further troubleshoot or correct this would be greatly appreciated.

Thanks to all.

John Kalmbach · 04-23-2009, 11:12 PM

With the Inverter and Charger both "disabled", turn the Starcool "on" with just the Onan running. After allowing the Starcool to operate for several seconds, and the Onan is running smoothly, "enable" the charger only, leaving the inverter "disabled".

If the problem you're having is intermittent, it could be that the battery voltage is low and the charger is drawing too much current and causing an overload/shut-down. Also, make sure you set the AC breaker size on the Inverter to 15 amps when using your Onan.

Let me know if this doesn't take care of the problem and we'll dig deeper.

John K.

AEJ · 04-24-2009, 02:57 PM

John: I disabled the charger and inverter with the generator running fairly smoothly( it revs slightly periodically) but when the starcool is started the inverter led for AC in turns off. It will blink on and then shut off immediately for a short time and continues blinking on in this mode. The display will show the AC in as 120v 0a 65hz. If I enable the inverter then the inverter starts and very quickly the AC in led comes on and stays on putting the inverter in the standby mode. When I disable the inverter the AC is now acceptable and runs the starcool fine. This leaves me where I need to be but I never had this problem before so I thought maybe there was a setting for pass thru of shore power that needed to be tweaked or that the generator needs a slight adjustment. Is there anything else I should check?

Thanks so much for your help.

John Kalmbach · 04-25-2009, 12:52 AM

Which Starcool do you have?

What happens when you enable the Charger with the Inverter disabled?

Is the AC breaker size set to 15 amps? (The default setting is 15 amps.) If it is set to 15 amps and you're still having the problem, try increasing it to 20 amps and see if that helps. I believe the Onan output rating is 23 amps.

To adjust the Breaker Size setting:
1. Set the DISPLAY switch to CONFIGURE.
2. Press Down MENU until Configure PROsine—Basic Menu appears.
3. Press the ENTER button once. AC Breaker Size appears.
4. Press Down DATA or Up DATA until the value you want appears.
5. Press ENTER to save this setting.

I think what might be happening is that the Inverter is actually helping the generator run the Starcool when it is enabled. Because the charger is drawing too much current, the voltage on the generator drops below the minimum voltage setting on the inverter and then shuts down for protection.

You mentioned that it had been working fine, so we need to determine what has changed. The battery condition is the most logical item that would change. Next would be the operation of the Onan, perhaps bad fuel or a fouled plug is not allowing it to run at it's peak, which it needs to do to operate the Starcool. If some settings on the Inverter were changed unknowingly, you may need to reset it to it's factory default settings and then program it for the correct battery size, type, etc...

We'll figure it out...eventually!

John K.

Greg In Austin · 04-28-2009, 09:18 PM

OK... it is late and I am tired, .... but I want to respond or I will forget.... BUT this sounds very similar to what we saw initially with the first inverter we had in our van. I don't remember now the make or model (but the story is in here somewhere).

Let me tell the situational differences first so you can ignore this if it sounds to far off.

We have a Honda 2000 generator, and a Danhard AC.

We had a problem with the initial inverter being able to recognize and share power from both battery and generator. The inverter tech support said it should be working. The AC tech support folks said it should be working. SMB said it should be working (and ot was them working with the tech support folks.

We swapped the inverter for another of the same unit. Same results.

This was almost the top of the line inverter.

We backed off one model to a less "smart" model... and everything started working.

I think it is the Prosine 2.0 we have now. The key for us was the powersharing settings. Once we got those correct, there have been no hiccups.

AEJ · 05-01-2009, 07:58 AM

John,

I'm not sure what starcool I have. It runs on 12v or 110v but I didn't know there were other variations. Where do I find that information?

When the inverter is diabled the and the charger is enabled it works fine as long as I have the inverter on when I start the starcool. If I then disable the inverter it will now continue to recognize the AC in as good and will charge the battery.

The AC breaker size is set to 15amps. I'll check later if setting it at 20amps changes anything.

Finally, what changed was I had a problem w/ my original prosine and it was replaced in September by SMB. I thought maybe some setting was different than the original which never had that problem. It might be that I need to have the onan generator serviced, although it seems to be running fairly smoothly.

Thanks again,

John Kalmbach · 05-02-2009, 01:21 AM

I just noticed that your SMB is an '06, you should have the Starcool III, which cools using the engine compressor or the 110 volt compressor.

If changing the AC breaker size to 20amps doesn't help, and if all is okay once the Starcool starts with the Inverter enabled, it sounds like the AC in voltage/hertz settings still need to be adjusted. Try setting the low range as low as possible and the high range as high as possible. I know you've already set the low range, but confirm the high range is as high as possible too.

Also, to confirm the generator is operating properly, turn on the Starcool with only the Onan running. Make sure both the Inverter and Charger are disabled. You only need to run the Starcool for a minute or so. If the Onan will not operate the Starcool with the Inverter disabled, then it sounds like the Onan may need to be looked at. You may have already tried this, I just want to be sure the Onan is not the problem.

Thanks,

John K.

AEJ · 05-05-2009, 12:18 PM

John:

I changed the breaker size to 20amp but that was not a solution. When I disable the inverter and charger the starcool causes the AC in to immediately shut down. I also set the low and high transfers to their extremes without getting a positive result. If I enable the inverter then the starcool will run fine. I can then disable the inverter and everything will continue running including the starcool. I don't care for the local onan (rv) dealer so I'm not rushing to go and have them service the generator.

Sooner or later I'll have to get it serviced but in a previous 12 yr old Roadtrek w/an onan generator I only serviced it when the muffler finally rusted and broke. It ran a 110v airconditioner and any other appliances I needed. Mine seems to run pretty smooth but it may need to be tweeked a bit? I've checked the oil and it looks like new. I haven't changed or cleaned the airfilter, so I'll take that out and check its condition.

thanks,

Rustywolf · 02-01-2010, 04:48 PM

Al - Did you ever resolve this? - Rusty

AEJ · 02-01-2010, 10:10 PM

Rusty, I haven't solved it but things have gotten worse since I wrote this. The inverter no longer allows me to charge my house battery when I'm plugged into shore power although it still inverts and I can run my generator but it won't charge the house battery either due to the inverter. I'm just about to take it to a local RV service guy who has worked on a few SMB. I have a standard converter that I'll have him install unless he can send out the prosine and have it checked. It is only 1 year after SMB got a new one from them and I'm having trouble with it. I'm going to send it out and hope its cheap to repair. I'll post again when it's resolved. I'll deal w/it very soon.