Wiring a reversing switch

Nov 26, 2008
1,966
Endeavour 42 Cruisin
My mascerator pump needs a bit of priming each time I want to pump overboard. When I installed it, tech support was OK with running it backwards to prime and that does work.

Currently, I have a jumper wire that I use to temporarily reverse polarity to prime. I would like to install a switch.

I bought a Cole Hersee DPDT 25A switch with 6 terminals. I contacted Cole Hersee tech support and they said someone will get back to me to help me. That was 3 months ago.

So, how do I wire this 3 position switch so that middle is off, left is pump in and right is pump out. The wiring is a simple Red/Black 2 wire setup.

Thnx!
 
Jun 27, 2014
117
Jeanneau Moorings International 50 Everett
Power (red & black) come in to middle pair of terminals. Pump connects to one outer pair of terminals. This pair also connects to the opposite end, but with wires crossed, so power and ground get reversed.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
Mascerater pumps are vane type and running them backward will significantly reduce the life of the impeller FWIW
 
Oct 30, 2011
542
klidescope 30t norfolk
Kinda but the opposite red and black go to middle , two terminals then red and black ;hot and ground go to one side. Then that same red makes an x over back of switch to opposing terminal and black ground does the same

Red + o. o. Black -

Pump. o. o. Pump black

Black- o. o Red +

o = terminal back switch
 
Last edited:
Nov 26, 2008
1,966
Endeavour 42 Cruisin
Back to my question...
I drew a crude wiring diagram and attached it as a pdf. The red/black leads on the left are reversed from the red/black leads on the right. They tie together going into the pump and the switch position will determine which pair/polarity runs the pump?? Switch in the middle position is off.
 

Attachments

Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
I sent this to a consult client who was trying to wire up a reversible oil change pump (don't forget fusing).. Just be sure your DPDT switch can handle the motor start-up loads, potential for locked rotor, and that the manufacturer is okay with reversing the vane pump......

 
Nov 26, 2008
1,966
Endeavour 42 Cruisin
Tech support for the pump didnt seem phased when I mentioned it. The pump is supposed to be self priming. I installed it about 6" above the waterline with a head of about 2' and it will not prime from the holding tank. So I run it in reverse from the thru hull just enough to get a prime that way, which works. Not sure why because the head is slightly more. Perhaps sea water pressure that pushes the water within a foot of the pump. Once primed, it sucks sh*t very well.

Thanks for the help everyone.
 
Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
[QUOTE="Ken Cross, ...Ron20324 get's the prize.[/QUOTE]

Oh, not really. He wanted his to work left and right. I showed him up and down...
 
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Jan 7, 2017
92
beneteau 36 new london
Please confirm this same setup would also work to reverse current flow direction of a DC-DC charger.

So one side of OFF position would charge from Bank1 to Bank2, the other side from Bank2 to Bank1.

Obviously the continuous amp rating of the switch needs to handle the max current, proper fusing, etc.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Please confirm this same setup would also work to reverse current flow direction of a DC-DC charger.

So one side of OFF position would charge from Bank1 to Bank2, the other side from Bank2 to Bank1.

Obviously the continuous amp rating of the switch needs to handle the max current, proper fusing, etc.
John,

You cant reverse the current flow through a DC to DC charger they are one-way devices, like a diode.. If you would simply explain the use you are after, I can help you pick a device. If you continue to be evasive then I can't be of any help. There are lots of DC to DC methods of charging but they all have idiosyncrasies and may or may not be suitable for the application for a myriad of reasons.
 
Jan 7, 2017
92
beneteau 36 new london
Sorry I wasn't more clear.

The above discussion and diagrams are about reversing polarity by swapping + and - wires.

I meant being able to "turn around" the one-way-flow device, not internally but by reversing the positive input and output wires rather than + and -.

Is that clearer?

I'm not trying to be evasive I promise, the scenario is that usually Bank2 is charged from Bank1, but I want when appropriate to be able to charge from Bank2 to Bank1.

I could swap the physical wires using color-coded welding quick-connects, but seeing this DPDT wiring diagram makes me think it could be done with a suitable high-amp switch in the same way, or if necessary a remote relay/solenoid.
 
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Jan 22, 2008
8,050
Beneteau 323 Annapolis MD
Sorry I wasn't more clear. The above discussion and diagrams are about reversing polarity by swapping + and - wires. I meant being able to "turn around" the one-way-flow device, not internally but by reversing the positive input and output wires rather than + and -. Is that clearer?

Not really clearer. Are you saying you want to reverse the direction the pump is flowing? THAT is what we've been telling you.
I'm not trying to be evasive I promise, the scenario is that usually Bank2 is charged from Bank1, but I want when appropriate to be able to charge from Bank2 to Bank1. I could swap the physical wires using color-coded welding quick-connects, but seeing this DPDT wiring diagram makes me think it could be done with a suitable high-amp switch in the same way, or if necessary a remote relay/solenoid.
THIS sound like something all different. You are not going to charge one battery by connecting it to another battery. As long as they are connected in parallel, they should both be charged the same. Or, do you have an ACR in there that you're not telling us about? Whatever it is you are asking, it is not coming across with your nomenclature.
 
Jan 7, 2017
92
beneteau 36 new london
do you have an ACR in there that you're not telling us about?
Not an ACR that simply connects two banks, but a more specialized combining device that only allows charging in one direction. My whole point is that (I think, my whole Q is simply asking for confirmation of this intuition) this switch layout can control the direction of that flow.

You are not going to charge one battery by connecting it to another battery.
Why not? Let's replace the word "charge" above with "allow current to flow". If bank1 has a higher voltage than bank2 and the two are connected, for example by a Balmar (ex-Heart) Echo Charger, my understanding is current will flow from the former to the latter until their resting voltage is equalized. Is that not the case?

Other DC-DC solutions that are "one-way" and work like this include Balmar's Digital Duo, intelligent battery-to-battery chargers, for example Sterling or Mastervolt..., and Power-Gate battery isolators from PerfectSwitch.

Now of course several of these devices only combine when they sense a multi-amp charging source active on the source bank. Others can be keyed to ignition or a manual control switch.

But some simply combine when they detect a voltage higher than a setpoint, and isolate when it drops. But that's beyond the issue at hand.

Are you saying you want to reverse the direction the pump is flowing? THAT is what we've been telling you.
The original discussion is about wiring a DPDT switch in order to reverse polarity, in effect swapping + and - wires more easily than doing so physically.

Same sort of thing is done with golf cart forward-reverse controls.

I am asking for confirmation that the same schematic will allow for swapping around the two positive leads of (for example) an Echo Charger. One wire, usually from the Primary/House bank receiving charge input, is "IN". The other, usually to a smaller Reserve/Starter with no other charge source, is "OUT". The third is to common ground and does not get switched.

So using a suitably sized DPDT switch or solenoid/relay should enable remotely "turning around" the directional flow of such a device, in position1 current is allowed to flow from bank1 to bank2, in position2 from b2 to b1, off means no combining.
 
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Jan 7, 2017
92
beneteau 36 new london
And I completely acknowledge there are lots of detailed issues around the "big picture" context of my idea, which may well run counter to what should normally be done on a boat.

To keep this thread from going off the rails, I'd appreciate our keeping things to the switch wiring scheme, unless correcting an obvious mistake in my underlying assumptions.
 

LloydB

.
Jan 15, 2006
806
Macgregor 22 Silverton
All that the switch does is change the polarity of the conductors leaving the switch body TO the motor, the supply current does not change. One would hope that it would be a momentary switch so that it couldn't accidentally be turned on and remain in that mode. A dpdt DC relay activated by momentary switch might be a preferable but more problematic solution.
 
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