Exhaust alarm connection

Jokani

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My senior moments are getting more frequent.

At the moment I have an exhaust alarm wired to the fuse board, which means I need to remember to switch it on.

I was rather it was fool proof and wired directly to the engine control panel. But I have no idea of how to go about this.

Can anyone point me in the right direction/ If it helps I have attached an MD2B wiring diagram.

md2b-wiring-diagram.png


md2b-wiring-diagram-cable-marking.png
 
On the back of the key switch there is a green wire . Connect to the same terminal as the green wire
BUT
Check that this becomes "live"when the engine is switched on ...... the diagrams are not very clear but I found clearer one on Bluemoment
 
I tried to complete this yesterday, but I found a number of green wires:

engine-panel.jpg


I tried putting an amp clamp meter on to each of the green wires in turn and switching on/off the ignition, but I couldn't detect a jump in amps to determine which one carries a live current when ignition is on.

There is one green wire that connects from the switch to the orange 'on' light, but I couldn't detect a current. That would be my guess but with 5 green wires I did not want to start cutting without being reasonably sure.

Are you able to help further VicS?
 
Why not use a voltmeter to determine which ones become live with the ignition on - this will allow you to determine the connector on the ignition switch that goes live when switched on - then just connect to that.
 
Why not use a voltmeter to determine which ones become live with the ignition on - this will allow you to determine the connector on the ignition switch that goes live when switched on - then just connect to that.

I did try removing some of the pull of plugs to do that, but even with some force they wouldn't budge, I was afraid that if I used any more I would break something.

And I couldn't get my meter probe in, so I reverted to the amp clamp which was not successful.
 
Is it a DC clamp on? They're relatively rare and much more expensive than AC (mine was near £100 but has proven its worth more times than I can think) and when I was looking typing in "DC clamp on meter" bought up loads of meters which were DC, but only with the probes....
 
I tried to complete this yesterday, but I found a number of green wires:

engine-panel.jpg


I tried putting an amp clamp meter on to each of the green wires in turn and switching on/off the ignition, but I couldn't detect a jump in amps to determine which one carries a live current when ignition is on.

There is one green wire that connects from the switch to the orange 'on' light, but I couldn't detect a current. That would be my guess but with 5 green wires I did not want to start cutting without being reasonably sure.

Are you able to help further VicS?

Why not use a voltmeter to determine which ones become live with the ignition on - this will allow you to determine the connector on the ignition switch that goes live when switched on - then just connect to that.

I did try removing some of the pull of plugs to do that, but even with some force they wouldn't budge, I was afraid that if I used any more I would break something.

And I couldn't get my meter probe in, so I reverted to the amp clamp which was not successful.


Use a voltmeter to check that the green wire on the ignition switch becomes energised when the switch is in its normal running position.

You dont need to cut any wires just check that you get 12 volts when its on. Hold the negative meter probe onto the blue wire ( blue is negative ) somewhere convenient and touch the positive probe on to the terminal on the switch or one of the green wires connected to it.

Now I have seen the photo I am happy that it will be ..... so connect your alarm to the same terminal on the ignition switch as the green wire.
 
Use a voltmeter to check that the green wire on the ignition switch becomes energised when the switch is in its normal running position.

You dont need to cut any wires just check that you get 12 volts when its on. Hold the negative meter probe onto the blue wire ( blue is negative ) somewhere convenient and touch the positive probe on to the terminal on the switch or one of the green wires connected to it.

Now I have seen the photo I am happy that it will be ..... so connect your alarm to the same terminal on the ignition switch as the green wire.

Many thanks for your help once again VicS, just to be sure this is the correct terminal:

wire.png
 
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Many thanks for your help once again VicS, just to be sure this is the correct terminal:

wire.png

Well more or less. Thats actually the power supply to the temperature gauge. follow it down you get to the to the charge warning light then continue down you get to the ignition switch. Follow the green the other way and you get to the oil pressure warning light then I rather lose track of it although it also supplies power to the tacho and the instrument illumination switch

Basically you can connect to anywhere along that bit of wiring, wherever is most convenient but directly to the ignition switch would be preferable. There should be unused provision for an alternator warning light connection that may be useful.

( note that the wiring to the instrument illumination bulbs is also confusingly plain green !)
 
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Sorry - Nope !

Read the questions and answers against this item on the Maplin website and you will see the clamp multimeter reads AC current only.

....and it's not the first time i've seen a misleading item description on the Maplins website.

I think the Maplin Answer is incorrect and the UNI-T UT203 does read DC Amps, here is a review demonstrating it, you only have to watch the 1st 30 seconds.

https://www.youtube.com/watch?v=96d5-APZhww
 
I have a Dilog which was the only one around at the time, but plenty of reviews on Amazon US describing the uses in solar etc, so definitely DC. I have to say I don't use it often but I now wouldn't be without it.

It will try to read currents low down, but don't expect accuracy, just an indication of current flowing at the milliamp level. My Dilog will "self calibrate" at low levels, so the display will move the decimal point left to show low currents and voltages. I also used it to check for harmonics from my alternator (it has a frequency setting too). If you have solar it's an essential tool
 
On the back of the key switch there is a green wire . Connect to the same terminal as the green wire
BUT
Check that this becomes "live"when the engine is switched on ...... the diagrams are not very clear but I found clearer one on Bluemoment

Where did you find 'clearer' wiring diagrams on blue moment? I'm trying to re-wire my old (unused for 30years) MD2b and I can't figure out the wiring diagram in the manual.

Thanks
Jeremy
 
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