Cranking relay terminal AI ?

[Waterhouse]

So I’m trying to do some testing on my mep803. In the TM, it says jumper a wire to the “cranking relay terminal AI”. Of course, they don’t tell you where that relay is or which terminal would be AI. (If there’s more than one) I’m guessing it’s just 24V +, but I don’t want to screw anything up. Can anybody shed any light on this?

 

[nextalcupfan]

I went over the schematic and it looks like the K2 Cranking Relay is near the K18 Pre-Heat Relay.
That means its behind the wall in the main control box.

My guess is somewhere in here, I cant say for sure because I've never had to mess with it.
K2 has 4 terminals, A1 terminal has wires 109F, 109E, and 109L going to it.

 

[Waterhouse]

I have the cover off. In your pic, under the big row of terminals in the center is a solenoid. It looks like a ordinary car solenoid. I’m thinking that is it, but again I don’t want to get it wrong.

Im testing the interrupter on the right side of your pic. It is an AC relay. Do you know if it is operated by DC volts? That’s what I’m guessing, but I’m not real good with this stuff.

 

[nextalcupfan]

The K1 AC Circuit Interrupter should be run off DC but I'm not sure.
One of the solenoids is the preheat relay, you should be able to tell that pretty easy because the wires going to/from it are huge.
In the main panel every relay location is labeled, isnt it the same in the other box?

 

[kloppk]

The Contactor (AC Relay) is operated by 24 volts DC.

There should be stenciling next to the two smaller relays in that compartment.
K2 is the Starter Relay (solenoid)
K18 is the PreHeat Relay (solenoid)

Here is a pic of K18 the PreHeat relay and the stenciling near it.





Here a pic pointing out the location of K2 & K18

 

[Waterhouse]

Ok, when I wiped the dirt off, I found the K18 and K2. lol. Of course, I didn’t know what they were anyways, so you were a big help. I jumpered the wire and tested the interrupter. The good news is it works. The bad news is it doesn’t work from the panel switch. Let me correct that. It works from the switch when the jumper is in. So that tells me the switch is OK.

Where would you look next?

Note, the interrupter light does not come on even with the jumper in place. Not sure if that’s important. (The bulb works)

 

[Guyfang]

Every Electrical Component on this set is labeled. What it is, and mostly the terminals on the component.


Im testing the interrupter on the right side of your pic. It is an AC relay. Do you know if it is operated by DC volts? That’s what I’m guessing, but I’m not real good with this stuff.

Yes its a DC controlled relay. I sent you a snapshot of the relay schematic, to your OTHER thread concerning this problem. You need to stop cross posting of problems.