Old switch panel

[chic014 0]

Hi all,

 

Another question from me. I've pulled out my old switch panel that wasn't wired in and trying to figure out how the battery monitor part of it works.

 

It looks like its from the time when you made your,own switch panel from switches wire etc.

 

I've figured out the switches easy enough.

The small board between the rotary switches and the back of the LCD display has a burnt out capacitor on it. Any idea what that board does? Looks like it has a transformer on it?

 

With the ammeter part of things in assuming I need external bridges. Is there anyway to know what resistance,I need to make the ranges read correctly?

 

I'm pretty confident I can figure it out if I know what does what but no part numbers or anything to help me along so any tips appreciated.

 

Or,should I just flag and buy a new one. Ideally could keep this one as it fits nicely.

[chic014 0]

Sorry here's the photos

[wheels 543]

Hmm, firstly, I would be very cautious about using this panel. None of the components will handle high current, of which you would normally have running on 12V circuits in a boat.

If you have a boat you want an EWO for, this panel will not pass. Providing the electrical inspector looks of course.

Anyway, so firstly, the transformer is part of the circuit that drives the display itself. I doubt a capacitor is "burnt out". Something burnt would more likely be a Resistor or Diode.

This display requires a Current sensing bridge. The main 12V supply connects to each end and two fine wires send the small voltage signal to the display unit.

[too_tall 15]

Wheels, that panel is not so terrifying. Its all fused, which is a good start ( although I prefer breakers, but hey, they do the same job more or less ). Depending on the electrical loadings, this panel may be perfectly within its capabilities current wise. Those switches don't have immediately obvious current markings on them, but if they are the same as the switches I have seen on a friends yacht, they can range from 5a to 32a. Suitable for most applications on a yacht.

 

In a tidy installation, its better than I have seen on many yachts.

 

Why do you say that an EWO inspector would not pass it?

 

The shunts for the display may be around somewhere if your lucky. Otherwise it could be a bit of fun finding what resistance shunts you need for the ammeter to work well ( remember that ammeters are only volt meters measuring the voltage drop over a known resistance shunt ).

 

If it is indeed a cap which is burnt then its quite likely that the display device has been subjected to a significant over voltage event. Maybe someone tried to connect 24v to it when the display driver is designed to operate at 12v pre transformer ( or worse, 240v to it ).

[banaari 27]

Hazarding a guess I'd say the board with the transformer on it and suspect capacitor is some kind of DC-to-DC voltage converter.

[wheels 543]

Why do you say that an EWO inspector would not pass it?

All terminals must now be screw type. No spade connectors.

It comes down to whether the inspector actually looks of course. Plus if EWO is not required, then it is not a problem.

[chic014 0]

Thanks for the replies.

 

No ewof here,and will be used on a relatively small electrical system. I think the board with the burnt cap must be stepping down the voltage from 12v to whatever the display wants. Maybe 5v or 9v?

[wheels 543]

Yep it should be 9V.