Retrofit hour meter electrical feed

slipknot

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I have the usual blank display on my volvo 2030 panel. I have bought a very nice mechanical counter and run it for a couple of weeks at home to bring it up to more or less the right hours. I have read many posts where people have made the electrical connection to the ignition switch, and I agree that wouldn't be a bad place to power the counter from. I would b prefer to take the supply from the output of the alternator, operating the counter only when the engine is running. Has anyone done this and could you tell me exactly where you pick up the supply on the alternator
 
I have the usual blank display on my volvo 2030 panel. I have bought a very nice mechanical counter and run it for a couple of weeks at home to bring it up to more or less the right hours. I have read many posts where people have made the electrical connection to the ignition switch, and I agree that wouldn't be a bad place to power the counter from. I would b prefer to take the supply from the output of the alternator, operating the counter only when the engine is running. Has anyone done this and could you tell me exactly where you pick up the supply on the alternator

The alternator output is connected directly to the battery all the while the isolator switch is on....so an hour counter connected to it will run all the time the main isolator is on , not just when the engine is on, except perhaps if you have a diode splitter.

The key switch is the only sensible place to connect to as far as I can think. The red/blue wire from the key-switch to the tacho, electronic module and any extra instruments fitted is the wire you need to connect to.
 
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I have an MD2020D so should be the same electrically.
I've mounted a counter in the engine bay - much easier and more convenient than outside! - and connected to alternator terminal D+/61. This has a brown wire and a blue/red wire on already. See diagram page 41 of engine manual. The blue/red actually goes through to the same point VicS mentions (becomes red/blue at the multi way connector apparently), but it has a ballast resistor in it (for alternator start up excitation), and (at least with my counter) the voltage after the ballast resistor is not enough to operate the counter if the switch is on but the engine not running. The brown wire is the ignition warning light.
This terminal is also used on my Jeanneau to operate the house battery charging relay, and the wire to that already had a spare female Lucar connector in it (to use for an electric windlass interlock), so I just had to plug in!
The counter neg goes straight to the earth stud on the alternator.
The counter runs only when the engine is running and the alternator producing an output.
 
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The alternator output is connected directly to the battery all the while the isolator switch is on....so an hour counter connected to it will run all the time the main isolator is on , not just when the engine is on, except perhaps if you have a diode splitter.

The key switch is the only sensible place to connect to as far as I can think. The red/blue wire from the key-switch to the tacho, electronic module and any extra instruments fitted is the wire you need to connect to.

Good job someone's thinking.......:o
 
Thank you all, and particularly Troubadour. That's exactly the advice I was looking for. Thank you very much for posting. Ian
 
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You may have to test terminal 61 as it does go to ign+ with the key on, via the ign lamp (or a ballast resistor) it may or may not work(switch off) - and subsequently changing the bulb for a different wattage may alter things,,,
However, another solution is the "W" terminal (if there is one, or tap into the raw ac output of the windings if you're a tecchy), via a rectifier diode. It may have the tacho sense feed on already, just fit a diode inline to the counter power feed. That DEFINATELY won't have power on until the alt is running!
 
You may have to test terminal 61 as it does go to ign+ with the key on, via the ign lamp (or a ballast resistor) it may or may not work(switch off) - and subsequently changing the bulb for a different wattage may alter things,,,
However, another solution is the "W" terminal (if there is one, or tap into the raw ac output of the windings if you're a tecchy), via a rectifier diode. It may have the tacho sense feed on already, just fit a diode inline to the counter power feed. That DEFINATELY won't have power on until the alt is running!

I wondered about using the W output with a diode. It may be necessary to add a smoothing capacitor ??

Picking up the feed from the key-switch to the taco is so simple and gives the same result, ie hour meter runs while key switch is in the run position, as originally that I cant see much point in anything that even slightly complicates the issue.
 
On my Lucas alternator, the warning light is shorted to earth before the field current is established and held at 12V once the alternator is excited.
On my dashboard, the hours enable is connected to the warning light, and also only runs when the engine is running and the alternator warning light is extinguished
 
I wondered about using the W output with a diode. It may be necessary to add a smoothing capacitor ??

Picking up the feed from the key-switch to the taco is so simple and gives the same result, ie hour meter runs while key switch is in the run position, as originally that I cant see much point in anything that even slightly complicates the issue.

That's how I did mine. Keep it simple Why would you have the ignition on if the engine wasn't running .
 
You may have to test terminal 61 as it does go to ign+ with the key on, via the ign lamp (or a ballast resistor) it may or may not work(switch off) - and subsequently changing the bulb for a different wattage may alter things,,,
However, another solution is the "W" terminal (if there is one, or tap into the raw ac output of the windings if you're a tecchy), via a rectifier diode. It may have the tacho sense feed on already, just fit a diode inline to the counter power feed. That DEFINATELY won't have power on until the alt is running!

I think you're complicating this. I've done it on both a 2020 and s D1 and on both the voltage is too low to operate the counter when it's not running.
Anyway it wouldn't really matter in reality!
 
I wondered about using the W output with a diode. It may be necessary to add a smoothing capacitor ??

Picking up the feed from the key-switch to the taco is so simple and gives the same result, ie hour meter runs while key switch is in the run position, as originally that I cant see much point in anything that even slightly complicates the issue.

Not if you want to put the meter in the dry in the engine bay rather than mount it by your control panel which is probably exposed outside.
D+ is the only accessible connection. Couldn't be simpler.
 
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it is possible to fit a new hour counter into the tacho in place of the defunct one.

www.dolcetto.org.uk/downloads/Replace Volvo Penta Hours LCD.pdf

The same instructions have I believe been published in one of the comics, PBO ??

I considered that but prefer a reliable electromechanical one where I can read it in comfort rather than kneel in the cockpit with my head on the floor trapped between the pedestal and the side! Also easier and cheaper.
 
I considered that but prefer a reliable electromechanical one where I can read it in comfort rather than kneel in the cockpit with my head on the floor trapped between the pedestal and the side! Also easier and cheaper.

Not a particularly good location for the tacho and other instruments either by the sound of it. Especially poor for something like the hour meter that you need to read regularly.
 
Not a particularly good location for the tacho and other instruments either by the sound of it. Especially poor for something like the hour meter that you need to read regularly.

Tacho and warning lights are reasonably visible but the small LCD hour meter needed viewing close up and it packed up as usual.

Edit - here's the new meter in an easy position in the boat and only about a foot from the alternator.
 
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I have the usual blank display on my volvo 2030 panel. I have bought a very nice mechanical counter and run it for a couple of weeks at home to bring it up to more or less the right hours. I have read many posts where people have made the electrical connection to the ignition switch, and I agree that wouldn't be a bad place to power the counter from. I would b prefer to take the supply from the output of the alternator, operating the counter only when the engine is running. Has anyone done this and could you tell me exactly where you pick up the supply on the alternator

I have just done it back in November so my memory is still fresh. I have an MD2-55 with the same problem afflicting every Volvo Penta hour counter, but I suppose that your alternator will be similar.
I found the right wire simply probing the voltage on the alternator using a tester with engine on and off. There is one small wire output that will go to +12V only when the engine is running, the large red wire will be always at 12V when the battery isolator is on. To the back of the meter you will feed the alternator +12V and the negative that you can bridge from any other instrument nearby since the Amps used by the counter are negligible. This way the counter will tick only when the engine is running. In my case the output is on a post on the top back of the alternator where there is one small red wire connected.
If you could post the picture of the wiring on your alternator I might be able to point it for you.
 
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