What is this?

things

New Member
i just got a neon sign transformer and it had this little box connected to the primary windings. I have an idea of what it could be (current limiting?) but was not sure. It says on it... neolite neon, OCM-B, Amps:1.5-2.5, Voltage: 240 AC and then all the aproval numbers and whatever. When i tap it, it feels like there is a spring of some sort in there (resistor?). does any one know what it is?

Thanks
 
hmmm, so i'm guessing no one knows what this is?. i have posted a similar question on another forum but they don't know what it is either?
 
Oh, i didn't notice the capacitor section there. when i tap it, it feels like there is a spring in there or something? It's says its an OCM, does anyone know what that stands for?
 
So what would the OCM do?
 
It monitors the output voltage, when it rises above a predetermined level, ( as would happen with an open circuit ) it disconnects the output.

This is a safety requirement in most areas, to prevent shock hazard and arcing/fire hazard if the neon tube was broken or a cap came free of the tube.

It often contains a fusible link on a spring, that burns open and the spring ensures the contacts are separated. THis is likely the vibration you noticed.
 
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You might need to disable it if you're going to use it to power a project.
 
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