I also have an Dual setup with the Mastervolt Alpha Pro II combined with Balmar
AT200 and the Balmar
Many alternators are setup to be regulated on the Postive+ side.
The Alpha Pro II is regulating the alternator from the Negative- side.
But it is often easy to modify the alternator from + reg to - reg.
The Alpha Pro II is also great for LIFEPO4
, as it can be configures just the way you want using an USB interface.
You know the yello wire is for the "charge lamp". I wounder if you can connect thus to the MDI instead of an relay. That way you get an error message when the Alpha Pro II is given an error.
Also I recommend connecting the white wire to the W output of the alternator.
Then the Alpha Pro II can read the RPM
of the engine
. This is useful if you have an really large alternator and what to limit the output on low RPM
The REG ON is also the SENSE wire. Its important that no other load is connected to this wire. I found that even if you have an Mastershunt connected, it still uses the reading on the sens wire. I wrote to Mastervolt asking about this, but never got an reply.
In my 1000AH Lifepo4
setup i let the BMS control the REG on signal
So in an high voltage event, it will not only disconnect the battery
, it will safely shut down the alternators also turning of the regulators.
When it comes to the temp sensor on the alternator, i found it difficult to get an correct reading using the Mastervolt sensor. The alternator would reach 120`C (using an handheld IR meeter) and the Alpha Pro II would only read about 85`C. Dont understand why they put an rubber layer around the sensor.
Anyway of the alternator is running to hot, especially in an LIFEPO4 setup then you can reduce the output using the "small engine" mode.
I configured it to give maximum output at 5500 RPM. Of course this will never happen so the output is permanently limited. I get about 250A out of 350A in this way, at 2300 RPM.
Using an Masterbus->NMEA2000 interface you can send all kinds of information to your display.
Volt Batt 1 (service)
Amp Batt 1 (service)
SOC Batt 1 (service)
Temp Alt 1
Field curr Alt 1
Volt Batt 2 (Start)
Amp Batt 2 (Start)
SOC Batt 2 (Start)
Temp Alt 2
Field curr Alt 2