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Discussion Starter · #1 ·
Hi all, I have a generic 7.5kva diesel generator. This thing stopped putting out voltage, now my question. It has a 20uf 250v half moon style capacitor that seems to be the culprit.
All the AVR unit I have been looking at have 4 or more connections.
Can I use one of these 4 pin units to replace my 2 pin?

Thank you in advance.
 

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It has a 20uf 250v half moon style capacitor that seems to be the culprit. All the AVR unit I have been looking at have 4 or more connections.
A little confusing... It it an AVR or a capacitor? Those are two different ways of regulating voltage. Do you have the generator model number? Did you mean Generac rather than generic?
 

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If the module only has two wires, it's a capacitor. If it has more wires, it's very likely an AVR. They are NOT interchangeable without significant modifications to the generator.

Capacitor:
Font Auto part Electric blue Fashion accessory Composite material



AVR:
Automotive lighting Sports equipment Gadget Headlamp Personal protective equipment


If you can't find a half-moon style capacitor, any capacitor with the same value can be jerry-rigged to it, such as this:

This is all assuming that the capacitor is faulty. There are some checks that can be done on the generator (winding continuity/Ohms check), as well as the capacitor (capacitance value check), among others, to help narrow down the root cause.
 

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Discussion Starter · #4 ·
A little confusing... It it an AVR or a capacitor? Those are two different ways of regulating voltage. Do you have the generator model number? Did you mean Generac rather than generic?
Well confusing yes, very much so...
Font Fashion accessory Musical instrument accessory Composite material Carmine

That is what it looks like. As for the brand it is unknown, hence the generic statement.
 

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Discussion Starter · #6 ·
If the module only has two wires, it's a capacitor. If it has more wires, it's very likely an AVR. They are NOT interchangeable without significant modifications to the generator.

Capacitor:
View attachment 12707


AVR:
View attachment 12709

If you can't find a half-moon style capacitor, any capacitor with the same value can be jerry-rigged to it, such as this:

This is all assuming that the capacitor is faulty. There are some checks that can be done on the generator (winding continuity/Ohms check), as well as the capacitor (capacitance value check), among others, to help narrow down the root cause.
What would the modifications entail? I am slightly handy, and know my way around tools. If there is a guide I can follow it...
 

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What would the modifications entail? I am slightly handy, and know my way around tools. If there is a guide I can follow it...
No personal experience. I've only seen AVR-type alternators being rewired to use a rectifier and capacitor in place of the AVR to supply power to the brushes. AVR-type to rectifier+diode is easier to do. The reverse is probably going to be impossible if the capacitor-only alternator is brushless. Anyway, it's a jerry-rigged deal and I wouldn't recommend going that route.
 

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Discussion Starter · #11 ·
If you are wanting the 20UF:
Thanks, but I am based in South Africa, and eBay takes a while to reach me, as eskom is currently supplying us with 12 hour rolling blackiiys daily.
 
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