Adjust Aladdin voltage connected to Surgeguard ATS 40250

[amphi_sc]

For years, my leg 2 voltage displayed on the Aladdin via the Surgeguard 40250 ATS is 2 to 3 volts higher than actual.  Even when leg 1 & 2 have to be the same coming in via a 30 amp dog bone, leg 2 is 2-3 volts higher than leg 1, and higher than what I read at an interior outlet.  Leg 1 appears to report more accurately.  Is there an adjustment to correct this mis-reporting on leg 2?  As I was doing my annual torque of screw terminals, I see a couple of pots on the board but don't know what they are for.  Where I'm plugged in now I measure a no load input voltage at the pedestal and outlets inside the coach at 125 / 126 volts.  Aladdin reports 125 + 129 ... Flagging the 129 as potentially high.  When I kick on an A/C on both legs the reporting drops to 123 / 125 drawing 16 amps each leg, and testing volts at outlets I read 123 on both legs.

Any way to adjust the 40250 so it reports more accurate readings?  I guess in theory the way it is now it could cut off power too early if the voltage rose a little more, or too late at another park that might really have a low voltage situation...but typically I would put my Hughes inline in that situation anyway to avoid brown outs.

[Frank McElroy]

Take a look at the procedure over on irv2.

https://www.irv2.com/forums/f54/false-high-voltage-indication-surge-guard-40250-rvc-174405.html

[amphi_sc]

Thank you Frank.  I will try this procedure when I move to a park with voltages in the 115 to 120 range.

[Frank McElroy]

It would be best to first measure the voltage at the pedestal with a good voltmeter and get as close to 120 volts as possible on each leg.  When doing this calibration, the display should read 120 volts on each leg after the calibration.  So, you wouldn't want an input voltage of say 115 at the pedestal showing 120 volts on the display.

[amphi_sc]

120V seems to make more sense.  The iRV2 thread said the techs told him 115v to 120v.  I wondered to myself how that wide range would work, but thought the factory techs must know what they are suggesting. 

However, I opened up my 40250 and the board does NOT have a J8 to jumper.  My board is laid out differently than the diagram posted on iRV2.  I called Southwire leaving a message on their tech support line but no callback yet.  The only identifying label is 34575-012 v4.5 on a long narrow dip chip.  Directly above that is an empty 3 pin header looks like labeled J2. No other headers to jump.

Edited June 5, 2023 by amphi_sc
Added picture of ATS cover

[amphi_sc]

Just following up with the response I got from Southwire ( who took over the 40250 line ) about my internal board that doesn't match the layout nor connectors.  i.e. there is no J8 to jumper to recalibrate.

My follow up query: 'Have you found anything out about how to calibrate the board I have as it is not laid out per your provided schematic?"

Southwire response: "I am sorry I have not.

The first one I sent was not even in our database I had to drag it out of one of my engineers.

I have reported that issue you have, and no one has spoken up with an alternative.

I know as soon as you upgrade then your Aladdin system will not work.

There is one solution and that is Silverleaf has a drop in that will upgrade your Aladdin system to their system.

Their system is compatible with our 40350 and 40450 units."

So I wonder where the internal board in my 40250 came from?