The 'E' Type Forum

Hello forum,

I have a working SU pump AZX 1307 with mechanical contacts. I have tried 2 varistors of the same type and an original capacitor and the spark intensity seems to be the same as per the foto.
I wonder if anybody can tell me if the spark I see is normal.

Greetings
Daniel

Hi Daniel, the blue device should be a capacitor, its job is to arrest the spark as on your contacts for the ignition points. Are there any words/letters/numbers on it? which may help identification, or do you have the original. Some capacitors (tantalum) do look like your photo. cheers John.

Convert it to electronic....a member here on the forum sells a small circuit board that fits in easily.....search for Marek.....Steve viewtopic.php?f=7&t=15667&p=174267&hilit=Marek#p174267

John, Steve,

Thanks for your input.
I am pretty sure the blue component is a varistor (no markings on it) which came from Burlen some time ago and it is dual polarity. I would like to keep it this way since as my spare, this pump should work on pos. and neg. earth.
As for the spark, it went away after I thoroughly cleaned all the terminals and contacts. So to answer my question: No , there shouldn’t be a spark easily visible.

Greetings
Daniel

Varistor or capacitor, both will do a similar job in this application. If you were to use a large non polarised capacitor such as those across the input to a power supply your pump would remain polarity insensitive.

A capacitor would be a better choice for suppressing RF radiation so would be my choice for this application.

In reality, both in parallel would cover all bases.