Zamp 30amp + Tripp-Lite controller questions

[Thorne]

We recently bought a 2011 SMB Sprinter RB110S and I'm still trying to figure out how the solar controller and inverter systems operate. Just replaced the two ancient house batteries with two high-end Duracell Ultra Platinum 105 Ah AGM RV/Marine batteries.

I see that the new model of the Zamp 30amp controller lets you manually select the battery type, but don't know how (or if it is possible) to do that on the older model. Looked online for manuals and videos but only found info for the new product.

Can't find any info on the older Tripp-Lite control panel / switch, so I'm not really sure what the distinction is between AUTO / INVERT and LINE / CHARGE ONLY.

Assumption 1: The LINE / CHARGE ONLY option is for using on shore power, where the inverter conditions the power it feeds to the 110 wall plugs as well as what it uses to charge the house batteries (and possibly the starter battery).

Assumption 2: The AUTO / INVERT option is for using battery power (and direct solar??) to run both the built-in 12v power as well as the 110 wall plugs and anything else wired directly to the inverter like the fridge, electric stovetop, hot water heater, etc.

Question A: What the heck is "boost voltage" on the Zamp controller? I found this page that says to use the 14.4 setting for Gel and AGM batteries and the 14.7 for standard lead acid - anyone know why?
https://janeandjohn.org/pages/Zamp-5.html

Question B: When the batteries are not fully charged and hooked to shore power why does the Zamp controller show 14.1 v when (as far as I know) AGM batteries in good condition aren't supposed to be charged at more than 14.0v? And with the new battery bank now showing as "full" in the battery condition list, why is it still charging at 13.8 on shore power per the Zamp screen when AGMs are supposed to have a float charge of not over 13.38?
https://deepcyclebatterystore.com/ho...ain-batteries/

Question C: I've wired a digital clock / thermometer / voltmeter into the 12v system, and it shows a higher voltage than the Zamp controller -- up to 14.5 when on shore power. Is that normal? In other words does the Zamp controller always display a lower voltage than something wired into the vehicle's 12v system?

[Scalf77]

First this is just the remote panel for the inverter.

Your first assumption is mostly correct, it does provide pass through of the shore power and power for the battery charger. It doesn't do any real conditioning of the in coming power. The charger should be wired to charge the house battery bank, it can also charge the starting ban if they are connected with a bidirectional separator or ACR type device that would connect the two banks in parallel

Assumption 2, the auto/invert does two things, if still plugged in and in auto, if you loose shore power, the inverter will take aver and supply power to the 110 devices. It does this by transfer switch relays, which move the ground bond from the shore power pedestal to internal ground neutral in the RV, as the inverter is now supplying the AC. If the shore power is available it could still be charging the 12 volt system, if the shore power is not available it will not be doing anything to the 12 volt power other than presenting a load if it inverting power from DC to AC. Solar power from the ZAMP controller would be consumed by the inverter if the load was more than what was being provided by the solar system. Other than that there is nor relationship between the solar and inverting systems.

Question A, I don't know much about that early ZAMP controller, so other than saying it should be replaced I'll refrain. You could email ZAMP, and ask for documentation.

Question B, If the batteries are not fully charged and hooked to shore power the Tripp-lite would most likely be in the bulk, or absorption phase. The absorption voltage should be over 14 volts, the Tripp-lite does not have an AGM setting, it should be at flooded and not set to Gel. I don't remember the exact voltage for the Tripp-lite flooded settings, it is a little higher, but I ran one for 10 years on a AGM. AGM absorption voltage is usually 14.3 or 14.5, check your battery for it's preferred setting. Also the Tripp-lite does come with a temp sensor that can be taped to the side of battery, if the sensor is being used the voltage set points will be adjusted accordingly. The ZAMP controller reads the voltage off of the same wire that it provides current with, this can make it less accurate, it also could just be off. The best way is to measure at the battery. If the temperature sensor is hooked up, but not attached to the battery, it will still be compensating the voltage based on the now air temp. Voltage settings are based on 77°F, temperatures higher reduce voltage, temperatures lower increase.

Question C, You will find that many devices are not really accurate when reporting voltage. A lot depends on the location and distance from battery you reading and the accuracy of the device. In any event you need to pick a location and take all your data off of that location, or you will confuse yourself even more.

I would add a good battery monitor to your future list of wants.

Hope this helps

[Thorne]

Scalf -

Thanks for the thoughtful response! It has been quite the puzzle getting this old SMB back to full functionality.

I hear you on the upgrade, and I plan on calling Zamp on Monday to see what information they can provide.