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Help with Master Switch

B

Bushcaddy

Well Known Member
Need some advice, so I come to the source:)

I am wiring up my Master Switch and after connecting the wires and hooking up a 12 volt power supply to the Master Contactor, I am not getting power where I think I should. My architecture is straight from Bob Nuckolls and my schematic can be seen here: http://www.donsbushcaddy.com/sitebuildercontent/sitebuilderfiles/n2celectricalschematic.jpg

I got my switch from Stein and it is one of those very nice Honeywell 8504 K65 locking toggle switches: http://www.steinair.com/images/store/switch6.jpg

When installed the switch should be off in the lower position, middle position is Batt and top position is Batt/Alt. I understand that the numbering on this switch may be different form Bob's Z drawings but I've tried it in many configurations and it seems wrong. With my architecture can anyone tell me which wire I should be connecting to which terminal on this switch? With the keyway up and looking at the screw terminals the numbering of the terminals is as follows: Left side bottom to top - 4,5,6. Right side bottom to top - 1,2,3. Thank you!
 
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Don,

I don't have the specs for that switch but...

If you have a multimeter, or continuity tester, I would spend some time learning how the switch is configured. You may also prove that the switch is good or faulty.

Good luck.

Bevan
RV7A wiring
 
master switch

I have a similar switch from Stein but have not wired it in yet. My master relay is from Vans. I noted that the master relay is closed with a ground input. This way there is no power on the cabin side of the firewall until the master switch sends a ground input to the relay. The switch is able to send more than one type of output from the different terminals. So you will have both a pwr and a grnd on one side and both pwr and a grnd on the other. The first step in the switch will provide a grnd signal to th master relay to close, this will make your pwr buss have battery power. The second step will provide battery voltage to turn on the alternator. If you check the master relay you should see battery voltage at the switching terminal, therefore a grnd input will activate it. If you check the switch with an ohm meter you will see that there is no continuity between the different terminals, so you can have two different sources and provide both a pwr and a grnd from one side to the other side of the switch. Clear as mud ? Later, K
 
Thanks

Everyone thanks for the input.

Ken, I wish I understood what you were saying...it's like Russian to me:)

Rocky, thanks for the link. I pulled the switch out and benchtested again and I came to the same conclusion as you...I get beeps from my continuity tester where I should, which is as according to my schematic, so that's the way I'll install it.
 
I agree

ken westlund said:
I have a similar switch from Stein but have not wired it in yet. My master relay is from Vans. I noted that the master relay is closed with a ground input. This way there is no power on the cabin side of the firewall until the master switch sends a ground input to the relay. The switch is able to send more than one type of output from the different terminals. So you will have both a pwr and a grnd on one side and both pwr and a grnd on the other. The first step in the switch will provide a grnd signal to th master relay to close, this will make your pwr buss have battery power. The second step will provide battery voltage to turn on the alternator. If you check the master relay you should see battery voltage at the switching terminal, therefore a grnd input will activate it. If you check the switch with an ohm meter you will see that there is no continuity between the different terminals, so you can have two different sources and provide both a pwr and a grnd from one side to the other side of the switch. Clear as mud ? Later, K
Click to expand...

Don,
I think Ken described the circuit very well. It's hard to get your head around the fact that you ground the master solenoid for it to energize.

What kind of power supply are you using? Most of the newer battery chargers won't work very good as power supplies. They won't put out any current unless they can "feel" a battery connected. Just something to consider.

Mark
 
Don, I have checked my switch and this is what I see. Consider the groove in the mounting area of the switch as up. Looking at the back of the switch, attach a grnd wire to the RH center pole and the master relay control wire to the lower RH pole. You should have continuity on these two poles on the 1st step of the switch. Connect a battery feed wire to the LH center pole and your alternator field feedwire to the lower LH pole. This will be active on the 2nd step only, but the RH center and RH lower will also be activated. I hope this will clear up the mud for you. Later, K
 
Getting Clearer

Mark: My power supply is a Pyramid, it is not a battery charger and does supply the 12 volts.

Ken: Definitely getting clearer to me. I think my wiring diagram is saying what you're saying but I'm not entirely sure. I currently have a wire that runs from the master contacter to pole 2 (RH, center) and it goes to ground through pole 1 (RH, lower). Reverse of what you indicated but I think accomplishes the same thing?? Or should it be the other way?

Then I have a wire that comes from the main buss power supply connection, goes through a 5 amp circuit breaker and connects at pole 5 (LH, center). The alternator filed wire connects at pole 4 (LH, lower).

So with the switch in the middle position, poles 1 and 2 connect and that allows power from the battery? With the switch in the upper position poles 1 and 2 connect and also poles 4 and 5 and this allows power from both the alternator and battery? And the alternator can be disconnected by pulling the 5 amp breaker or by moving the switch to the middle position?? Here's the wiring diagram again, it's a jpeg and you should be able to enlarge it to make it clear: http://www.donsbushcaddy.com/sitebuildercontent/sitebuilderfiles/n2celectricalschematic.jpg

Thanks...
 
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Don, if you take the wire from pole 2 and touch it to the airframe, does the contactor close? Just trying to diagnose if the problem is on the switch side or the contactor side...
 
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