diy solar

diy solar

You would think that I could use the cam switch as a simple two pole manual transfer switch but NOOOOOO!

offgriddle

offgriddle

"FOREVER BEGINNING"
Joined
Sep 21, 2019
Messages
1,452
Location
Oith
Ok, I purchased this three phase BAOMAIN, SW26-63/D303.3 cam switch switch in hopes that I could use it as a simple two pole transfer switch to supply 110VAC to a tiny off grid home by switching between generator power OR inverter power.

I tried "ohming it out" with my volt ohm meter so I could make a terminal connection diagram, but the only terminals that show continuity are 1 and 2.

There was no documentation provided and I looked online for diagrams and found nothing and looked on YouTube for instructional videos but found no videos posted in coherent English.

Note: I noticed a slight burnt smell from the switch but it in every other way appears to be new and never used out of the box.

Any Ideas?

OG

20210225_093949.jpgT
 
Don’t know the switch, but what is it rated for and what did you run through it?

I was looking for a 3 pole, 3 position switch, with one poition being off, for DC 45 amps and 100 volts, and I found a switch for more than that in AC, contacted the manufacturer to see if it could be used for DC since arcing worries me. I was told I guess so and did not use it. The company also sold many different types of three pole switches, so not sure what yours does by looking at it. Each different switch had a schematic.

A different transfer switch I have plans for but have not built, would energize a relay that cuts power to AC circuit breaker for the converter whenever the inverter is turned on. To me a transfer switch means something like that where a contractor relay is used.
 
Last edited:
chrisski said:
Don’t know the switch, but what is it rated for and what did you run through it?

I was looking for a 3 pole, 3 position switch, with one poition being off, for DC 45 amps and 100 volts, and I found a switch for more than that in AC, contacted the manufacturer to see if it could be used for DC since arcing worries me. I was told I guess so and did not use it. The company also sold many different types of three pole switches, so not sure what yours does by looking at it. Each different switch had a schematic.

A different transfer switch I have plans for but have not built, would energize a relay that cuts power to AC circuit breaker for the converter whenever the inverter is turned on. To me a transfer switch means something like that where a contractor relay is used.
Click to expand...
Hi, it's a 63 amp, 660VAC switch, but i must admit i did not spend a whole lot of time researching the specifications.The switch was less than thirty dollars US and I read the reviews and knew there would be no documentation included but thought i could figure it out when it arrived.
 
A "similar" switch is marketed by Blue Seas as a marine generator transfer...look there. The row of connections left to right in your photo are the 3 poles. I wouldn't use it for DC switching live circuits, it will arc and die, if the circuit is dead its fine for DC continuity.
 
Is it a two or three position switch? Could be position one generator, position two, inverter, position three off.

Also, are the six contacts the only ones or is there more on the other side? I would expect six contacts each for the hot, neutral, and ground for the generator and ground. If its only six contacts, I would expect it to be an on / off switch for one AC circuit, not two.
 

Attachments

  • 71iUxA0UVYL._AC_SL1200_.jpg
    71iUxA0UVYL._AC_SL1200_.jpg
    80.4 KB · Views: 33
Whinny said:
Try this as well...last photo....

Baomain Universal Rotary Changeover Cam Switch SZW26-63/D303.3D 660V 63A 3 Position 3 Phase with Master Switch Exterior Box LW28-63/4 : Amazon.ca: Industrial & Scientific

Baomain Universal Rotary Changeover Cam Switch SZW26-63/D303.3D 660V 63A 3 Position 3 Phase with Master Switch Exterior Box LW28-63/4 : Amazon.ca: Industrial & Scientific
www.amazon.ca
Click to expand...

thankyou, thankyou ,thankyou,THANKYOU Whinny, the terminal chart that you located and shared was precisely what I needed. :) OG
 

Attachments

  • .jpg
    .jpg
    80.4 KB · Views: 11
chrisski said:
Is it a two or three position switch? Could be position one generator, position two, inverter, position three off.

Also, are the six contacts the only ones or is there more on the other side? I would expect six contacts each for the hot, neutral, and ground for the generator and ground. If its only six contacts, I would expect it to be an on / off switch for one AC circuit, not two.
Click to expand...
Check out whinny's chart; this is exactly what the switch does and what I need. I am now going to use the switch in the system build, stay tuned ...
 
My switch like that is in my Winnebago...2 poles transfer the inverter hot and neutral main beaker circuit, the 3rd pole disconnects the converter when the inverter is on
 
Whinny said:
My switch like that is in my Winnebago...2 poles transfer the inverter hot and neutral main beaker circuit, the 3rd pole disconnects the converter when the inverter is on
Click to expand...
Ok got it about the 2 poles transferring between the inverter AC output hot and neutral and the shore power AC hot and neutral. Is the convertor you are referring to a 12 VDC power supply?
 
It refers to the standard WFCO R.V. converter/charger. I don't want that trying to charge the same battery I'm using to supply the12v to the inverter.
 
Whinny said:
It refers to the standard WFCO R.V. converter/charger. I don't want that trying to charge the same battery I'm using to supply the12v to the inverter.
Click to expand...
Why would it be a problem charging the battery while it is supplying power to a load?

This is my diagram for the cam switch showing the terminal connections, thank you again.
 

Attachments

  • 20210228_193013.jpg
    20210228_193013.jpg
    110.1 KB · Views: 25
offgriddle said:
Why would it be a problem charging the battery while it is supplying power to a load?
Click to expand...

Problem is more once the inverter tries charging itself via the converter when this inverter is plugged into shore power. At worst wasteful, at best dangerous. Usually you just flip the converter circuit breaker to prevent this. I left the circuit breaker on once, and my 15 amp battery charger ended up pulling at least 700 watts and I hears a clicking which I think was the self resetting circuit breakers located by the battery.

Another way to auto shut off the converter this is here:

 
chrisski said:
Problem is more once the inverter tries charging itself via the converter when this inverter is plugged into shore power. At worst wasteful, at best dangerous. Usually you just flip the converter circuit breaker to prevent this. I left the circuit breaker on once, and my 15 amp battery charger ended up pulling at least 700 watts and I hears a clicking which I think was the self resetting circuit breakers located by the battery.

Another way to auto shut off the converter this is here:

Click to expand...
Thank you for the excellent video. Yes, using a battery to charge itself would essentially be perpetual motion!
 
offgriddle said:
Why would it be a problem charging the battery while it is supplying power to a load?

This is my diagram for the cam switch showing the terminal connections, thank you again.
Click to expand...
I was thinking I had bought the wrong 3 position switch (like Whinney's) after realising I needed 2 "ins" and a common "out". I have not seen any such switches out there. I have looked at 2 position switches, but all I have seen are on/off, not on 1/on 2.
How did you physically connect 8/6 and 4/2. Did you insert a jumper between terminals or run both "outs" to an external terminal block? I hope my question is clear. Thanks
 
Last edited:
This switch turned out pretty easy to join the output poles to a common connection. Inexpensive and easy to wire and pretty much goof proof.
 

Attachments

  • SWITCH.JPG
    SWITCH.JPG
    120.4 KB · Views: 22
Levo said:
This switch turned out pretty easy to join the output poles to a common connection. Inexpensive and easy to wire and pretty much goof proof.
Click to expand...
Link please.

Does anyone know where there are instructions (not Utube) ?

The switches I have looked at Via post 6 do not provide any worthwhile info.

If it really is "goof proof" I need to put it in my shopping cart. ;)
 
Last edited:
WYtreasure said:
Link please.

Does anyone know where there are instructions (not Utube) ?

The switches I have looked at Via post 6 do not provide any worthwhile info.

If it really is "goof proof" I need to put it in my shopping cart. ;)
Click to expand...
There’s 120 volt AV 30 amp and 65 amp switches here:


Blue Sea sells a few switches that look a lot like the OPs link. I contacted them a couple years ago and they said it was made by Schneider.

The Blue Sea site has a lot if documentation if you go to the switch you’re interested in.
 
chrisski said:
There’s 120 volt AV 30 amp and 65 amp switches here:


Blue Sea sells a few switches that look a lot like the OPs link. I contacted them a couple years ago and they said it was made by Schneider.

The Blue Sea site has a lot if documentation if you go to the switch you’re interested in.
Click to expand...
Thanks chrisski,
I read the installation instructions for 3 of the switches.
The only reference to DC is in the installation where the manufacturer says make sure there is no electrical power to the wires while connecting.

This looks like a nice AC SWITCH which is NOT FOR USE WITH DC.

I would be very surprised if any of the cheap knock-offs are safe to use on a DC circuit. I believe they are AC ONLY.
 
WYtreasure said:
Thanks chrisski,
I read the installation instructions for 3 of the switches.
The only reference to DC is in the installation where the manufacturer says make sure there is no electrical power to the wires while connecting.

This looks like a nice AC SWITCH which is NOT FOR USE WITH DC.

I would be very surprised if any of the cheap knock-offs are safe to use on a DC circuit. I believe they are AC ONLY.
Click to expand...
I did not realize you wanted dc.

I emailed blue sea who contacted Schneider about those, and Schneider said they should be good. I can‘t remember if i asked for a 45 amp or 30 amp dc limit. Anyway, ‘should be’ is not good enough for me in a Rv install, so i did not buy those. I had planned on using this to switch solar panels to a circuit breaker prior to the SCC where four panels would be in parallel at 24 amps with a 30 amp circuit breaker, or four panels in series at 6 amps with a 10 amp circuit breaker. I abandoned that plan.

AFIK, all these different website switches I looked at that were similar looking are AC switches, although some are deceptively labeled with things like 120 volts and 65 amps, but makes no mention of DC, and sometimes there is no description.
 
You must log in or register to reply here.
Back
Top