SMX Board/Lo AC Reading

[0533]

I recently had my Chassis and House batteries replaced at Prevost Car in Jacksonville.

Great result other than the affect on my wallet.

But I have now noticed that I am getting a "Lo Ac" reading on my SMX screen on my galley SMX board for Heat and cooling.

Leon at Marathon said to: 1. press the off button 2. Press the off button a second time while holding both the up and down button at the same time. 3. This will show a reading on the screen. If the reading is at 100V or less press the up button on the SMX pad until the value is between 23 and 25.

I am unable to get my screen to show any values other than the temp and the desired temp setting when I follow this procedure

Has anyone had experience with this issue.

[jelmore]

Those (not quite right) instructions are for calibrating the AC line voltage. You have to know what the AC line voltage is and then see if your SMX control is off. You have to enter the programming mode by pressing off, then set. Then pressing the up and down keys at the same time will show the last two digits of the line voltage. And before I get in trouble with how to calibrate it, you should read page 7 in the attached pdf file "CruiseAir Controls.pdf".

The problem could indeed be low voltage from shore power. Does your control center (?) show a low ac line voltage on that leg?

This pdf file is handy for customizing your CruiseAirs on things like low fan speed, when the fan comes on, etc. Lots of settings to play with.

[0533]

Interesting Jim,

I followed the directions that i was given with no results.

I will give it a go by adding the Off, "SET" and UP/DN sequence to the plan this time.

What i believe happened at my end was when the house batteries were changed out the SMX board saw low power for more than 3 minutes which I have been told will require a resetting of the values.

My incoming power to the bus is fine, no issues there.

I am guessing that once I do the sequence you have suggested i will see a value of 10 = 100V or less, If I than press the up button I will want to adjust the value to 23 to 25. Question: Will I than press "SET" again to save the new values??

[jelmore]

I'd read the manual, again and again. I don't think I would adjust that setting on the SMX without being absolutely sure that it is indeed out of calibration.

[phorner]

FWIW, I would shut off the breaker to the SMX circuit for a good while. Then turn the breaker back on to see if it "reset".

Nothing to lose.....

[0533]

Have downloaded it and am now reading it carefully. I see that it explains how to get to these values and what the readings should be. On page 10 its explains the Line voltage and how to check what the readings are. Page 12 says use the down up key to adjust.

[adamdegraff]

Bruce,
for all things cruise air, I would call Johnny at AAP.

work 804-633-9454
mobile 804-380-6244

He is a great guy and knows this stuff better than anybody. Tell him the fiddle player told you to call him. He travels around the country teaching techs how to work on cruise airs. He's great!

See you in Florida next month?

~Adam

[adamdegraff]

what kind of batteries did you install? How much installed? I may be in the market. Though... now that I'm in warmer temps, I'm noticing a significant improvement in performance.

Take care,

Adam

[0533]

Hello Adam,

I have just returned from the bus. have had great success (for Now) with the directions on managing the SMX board. Reset the board to factory specs then did some minor tweaks to get the power and other setting the best possible based on incoming voltage.

This was pretty easy given all that can actually be done using the SMX panel for displaying values for lots of useful stuff.

I have an RVAC system that runs off two 115V 20 amp lines to the board. I needed to adjust the line voltage to meet this value.

Bruce

[lewpopp]

Bruce,

Did you consider getting Lifeline thru POG. There is a sizeable discount but it's too late now.