FrigoBoat AV12 12vdc compressor motor test.

[valeria]

Hi,
I would like to ask if I can test the compressor motor with an external power supply. The controller was damaged and I think I have repaired it but the compressor still doesn't kick.

The compressor label says 12vDC. There are 4 wires Brown, Blue, Black and Yellow.
Checked resistance between each. I have 0.8Ohms between Brown Blue and Black and 5.6Ohms between Yellow and any other wire.
Is this normal or do I have a shorted turns.

A sketch/diagram or wiring of compressor would be grateful.

 

[superheat6k]

Are these four wires direct to the compressor or to the controller ?

Ths might help ...

http://www.frigoboat.com/frigomanual.html

But no wiring diagram !

Found the manual as a PDF, but bad news the motor is an AC unit the controller converts the 12vdc supply to AC so that's why you have three fields with similar resistance. It doesn't state what AC voltage, but I reckon you would need their specific controller, sorry.

PDF here. http://www.veco.net/veco/sito/manuali/doc/Fmgb35new.pdf

 

[nigelmercier]

The control box contains an inverter that converts the DC input into AC, and I have reason to believe it is 3-phase. To test on 12V, you need a working control box.

 

[valeria]

Are these four wires direct to the compressor or to the controller ?

These 4 wires go from the controller to the compressor.

The control box contains an inverter that converts the DC input into AC, and I have reason to believe it is 3-phase

I am assuming the control box does some DC switching. There are no transformers or inductors or H-Bridges in the control box which is requirement to get AC from DC. So I am assuming its pure DC as the compressor label actually says (shown in image in post). My assumptions where that a pair of windings control the field and the other pair the armature similar to a battery hand driller.

 

[nigelmercier]

The control box contains an inverter that converts the DC input into AC, and I have reason to believe it is 3-phase[/I]

I am assuming the control box does some DC switching. There are no transformers or inductors or H-Bridges in the control box which is requirement to get AC from DC. So I am assuming its pure DC as the compressor label actually says (shown in image in post). My assumptions where that a pair of windings control the field and the other pair the armature similar to a battery hand driller.

You may be right, but my brief investigations led me to believe the control box produces pulses of DC split into 3 phases, a sort of quasi-AC 3-phase. I tried putting 12V across what I think were the common and one of the "phases", the motor went clunk and rotated a bit.

 

[valeria]

Hi Nigel,
I have followed the wiring to the control box. The Brown is internally connected to the +12V, blue to one SCR and black to another SCR. Yellow is connected to a small signal transistor with a narrow track on PCB indicating most probably a signal contact eg RPM .
I have applied 12v betrween Brown and 1 phase and fuse blew immediiately. Tried with the other phase and again blew the fuse.
So from your investigations I can see that the compressor is actually damaged- right?

I have emailed frigoboat tech support but am very dubious if I manage to get any feedback!

 

[nigelmercier]

The Brown is internally connected to the +12V, blue to one SCR and black to another SCR. Yellow is connected to a small signal transistor with a narrow track on PCB indicating most probably a signal contact eg RPM ...

I didn't go that far, if there are not three SCRs, then I'm probably wrong.

 

[valeria]

After more research and your help here, I concluded that the compressor is ok and the controller is still faulty.
To summarise: Compressor is driven by pulsed 12vDC. To check compressor I connected the + to Brown and short interval once the Blue then the black. The compressor was felt rotating.

This websitehttp://www.veco-na.com/technicalinformation/frigoboattechnicalinfo.html

has very good information. Confirming winding resistance is ok.
Older (pre-1995ish) four-pin controllers for BD2.0, 2.5, and 3.0 - The cable from the controller connects to the
compressor by means of a four-way plug that is a friction-fit onto four pins on the compressor, which are arranged
in a diamond pattern. The resistance reading from the bottom pin to either of the two side pins should read
approximately 0.2 ohms. The resistance reading from the bottom pin to the top pin should read approximately 3-4
ohms. There should be no continuity between any of the pins and the compressor shell.

So what I am after now is a PICTURE/PHOTO of the inside electronics as I have found a resistor near the Mosfet burnt and dont know the actual value.