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P-mag wiring with Vans DC Load center and the ACS key-switch

ao.frog

Well Known Member
Hi.

I'm installing dual P-mags on my Superior IO-360.
I'm also installing Vans DC load center EXP-2V and the ACS A-510-2 ignition switch (key-switch)

The P-mag wiring diagram says to connect pin 5 (+13,8 v dc) to the main bus via a switch and breaker.
I've installed two separate switches/breakers for this purpose, but here's the question:

Since I don't have a separate main bus, where schould I connect the wire from pin 5?
(I assume wire 5 is the primary power source for the P-mags?)

So far, my thoughts are to connect pin 5 to a pin on the EXP-2 panel which is always powered, for example the "clearance delivery pin".

Or maybe I schould wire pin 5 to the shunt or the battery? That way, the P-mags will be completely independent of the EXP-2 panel. And they are protected via the separate switches/breakers.

Second question:
Is it correct that the wires from the key switch to the magnetoes are the two shown on the P-mag diagram? (P-lead = "kill switch)

Or am I completely confused here??

In short: how schould I wire up the P-mags with Vans EXP-2 panel and the ACS igntion key switch?
 
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I don't have P-Mags but ....

I used the DC Load Center (Exp-Bus) and a key switch along with a Jeff Rose Electronic Ignition.

I do not have the drawings before me now and the work was done over seven years ago but I wired power to the Electronic Ignition via a SEPARATE/DEDICATED switch (fused). That toggle switch is just to the left of the Key Switch which I think that I wired per the instructions.

The main point here is that I chose to have ignition be INDEPENDENT of everything else electrical. That way if the Load Center went up in smoke, I still had electrons going to the engine for firing a set of plugs.

By the way, our RV6 tip-up DID leak and I DID get water into the Load Center once. I think I had to shut it off and fly home on the wing of a friend.

James
 
always hot

Although I am not using the DC Load center, I wired my ignitions to the battery bus, so they're always hot when the breakers are switched on. I think the logic that you don't want to depend on a DC Load center or anything else keeps a critical circuit dead simple.
 
Reviving an old thread.. I have the EXP 2 bus and want to do Pmags.. I’m not familiar enough with the exp 2 bus and I don’t have a a dedicated “normal” master contractor. how have others made these play well together?
I’m thinking I can supply power to the Pmags with outputs MB1 and MB2? If the EXP bus failed, then it’s on the internal generators anyway..
 
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Reviving an old thread.. I have the EXP 2 bus and want to do Pmags.. I’m not familiar enough with the exp 2 bus and I don’t have a a dedicated “normal” master contractor. how have others made these play well together?
I’m thinking I can supply power to the Pmags with outputs MB1 and MB2? If the EXP bus failed, then it’s on the internal generators anyway..

I just installed a new engine with dual p-mags with an EXP 2. I used the "ignition" circuit(and switch) to two 2amp breakers. Very simple and works as expected. If you want to call me, send me a PM and we can chat.
 
I just installed a new engine with dual p-mags with an EXP 2. I used the "ignition" circuit(and switch) to two 2amp breakers. Very simple and works as expected. If you want to call me, send me a PM and we can chat.

Sent you a message.. look forward to talking tonight.
 
I have had an ExBus2 and CPI electronic ignition for over two yrs. The ignition switches are completely separate from the ExBus for two reasons. First, I didn’t have enough circuits on the ExBus for everything and most importantly I wanted the engine separate in case the ExBus failed. Working well. I found the ExBus wiring kind of hard to understand a first but keep studying it and it will become clear eventually.
 
I have had an ExBus2 and CPI electronic ignition for over two yrs. The ignition switches are completely separate from the ExBus for two reasons. First, I didn’t have enough circuits on the ExBus for everything and most importantly I wanted the engine separate in case the ExBus failed. Working well. I found the ExBus wiring kind of hard to understand a first but keep studying it and it will become clear eventually.

There are several ways to skin this cat. The manual is a good resource and is pretty straightforward. S9 or "AUX1" is connected to the IGN switch on the ExBus2 version that comes with the switch bank. It's ideal for an electronic ignition that doesn't have an internal generator where you might want to use a battery backup. Pursuant to the manual, "With the backup battery option installed, this switch output is dual sourced, and will draw power from either the backup battery, or the master battery automatically using the strongest power source. The AUX 1 circuit is very good for powering automotive engine components that must be powered to insure engine operation."
 
Thanks for all the replies! I don’t have that switch bank, but I see that the IGN switch is one of the AUX functions. I think I’m going to use MB1 or MB2 because it doesn’t require a second switch. It is switched from the master, which is all I need. I don’t need the redundancy of a backup battery, as the P mags are self sustaining, and if the power circuit were to fail, it only effects starting, no danger of inflight engine quitting.
 
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