AGS things that bug me

[Neemer]

I cannot figure this out.

A few weeks ago we were at a fairground and plugged into 30 amp shore power. This was my first time dealing with 30 amp, so I wanted to see how my EMS would manage things.

Weirdness happened (or at least things I do not understand). At one point, and I think it was when I turned the microwave on, the AGS started the generator. Now, based on what I just read in the AGS manual, the AGS is supposed to be locked out whenever plugged into shore power, yet that happened.

Weirdness #2: Yesterday, again at a fairground, I had just unplugged and moved the coach into position to hook up the toad. Whilst I’m hooking up, I hear the generator start. I hadn’t been off shore power for more than a few minutes, so I know the batteries were still well charged. When I looked at the inverter remote, it was showing “Gen Run Fault” (which I understand is caused by terminating the AGS-commanded generator run before its preset duration).

My AGS is set to come on at 12.2V or when the HVAC calls for it. Yesterday, my HVAC was set to heat, and the temperature inside the coach was greater than the set points.

Can anyone make sense of this? I sure cannot.

 

[JRS]

Sorry..... of no help but following.

 

[Neal]

the AGS started the generator. Now, based on what I just read in the AGS manual, the AGS is supposed to be locked out whenever plugged into shore power, yet that happened.

Based on statement 3 below, you probably spiked your voltage and that triggered AGS to come on. Voltage spikes can be severe such as from microwave use (on inverter circuit) and maybe your 30A supply couldn't keep up. OR you browned out and didn't know it and that's where AGS will instantly come on. Were any roof units (heat pump or cool mode on?)

When I looked at the inverter remote, it was showing “Gen Run Fault” (which I understand is caused by terminating the AGS-commanded generator run before its preset duration).

Whatever turns the GEN on should turn it off or you get a fault. If AGS turns it on, don't touch it, let AGS turn it off.

My AGS is set to come on at 12.2V or when the HVAC calls for it. Yesterday, my HVAC was set to heat, and the temperature inside the coach was greater than the set points.

Tough situation as mentioned above, voltage can spike severely. This is why I use a LBCO of 11.0, yes 11.0, because Keurig in the morning when boondocking can spike me into a cutoff. I have a ME-BMK so I have state of charge available for triggers such as the GEN to come on at 65-70% (whatever I have set for my needs). I don't know that I'd use voltage for a AGS trigger unless really low such as 11.5.

 

[jaydee325]

I think some of the problem comes from your abnormally high auto gen start (AGS) voltage at 12.2. It does not take much load to drop voltage on your batteries to that value. My Magnum inverter/charger manual suggests 11.5V for AGS and this was confirmed by the tech at the dealer who gave me a walk through of my coach at purchase. Remember, under load, the battery voltage drops depending on the load applied. If your batteries read 12.2 volts under load and you removed that load, again depending on how much load you had, the batteries probably will recover to a no load value close to full charge voltage (12.6 no load volts).

Even when we are dry camped, I don't use AGS. We're usually running air conditioning anyway, so the batteries get charged by default. If cold, I just run the hydronic heater and monitor battery voltage myself. A few hours of generator time in the morning and evening keeps the batteries up for us.

A month or so ago, we were parked with 30 amp. My wife was making dinner. One air conditioner was on and she had food in the toaster oven. Current draw was an indicated 28 amps. She put something in the microwave and I thought, "this will be interesting". She turned the microwave on. Everything continued to run fine. I checked the Magnum inverter panel and it showed that the energy management system (EMS) had transferred the additional load to the inverter/batteries. Once the microwave shut off, the Magnum control panel showed 28 amps again and that the batteries were charging.

 

[Neemer]

Were any roof units (heat pump or cool mode on?)

Oh yeah, I was playing it as though I was on 50 amp. I wanted to see what would happen. I fooled around and found out.

I checked the Magnum inverter panel and it showed that the energy management system (EMS) had transferred the additional load to the inverter/batteries.

Thanks for posting that. I saw that too in my first instance. I was like, “Wut?”

This has been very instructional for me. Thanks all.