Hi all,
I'd like to switch 6kV/~1mA (from a potted brick HV PSU) between two terminals. This is only a temporary arrangement for testing. I was thinking of using a modified relay mechanism (from a broken, line power rated relay) as in the schematic below. The teflon piece is attached to the relay swing arm to both extend the swing range and to isolate the relay mechanism from the 6kV.
Is there any reason not to try this? I am mainly concerned with inductive kickback from the switching destroying my 6kV PSU. Is that likely to be a problem in this scenario?
Thanks!
Gus
There are several reasons, to use a proper and intended-for relays, instead of your DIY solution:
1. 5kV will quickly destroy usual low voltage relay contacts. Use HV reed relays with gas filling, instead
2. Proper HV separation between HV contacts and your steering circuit is required, at least for safety reasons.
Otherwise, the HV will arc over to your circuit and destroy it, and may as well also harm the user, that is YOU.
3. Take handling of HV very serious, please.. so don't do such experiments, only to save cost!
The HV PSU will not be affected by induction, where should that come from?? The inductivity is on the steering side only.
I remember, that these old HV reed relays (inside the FLUKE 335 calibrator) are still available, so look for one of these, they are really huge, but are able to switch 5kV, 7.5kV, 10kV at reasonable power figures, so 1mA should be no problem. The outer switching coil is available for 5V, 12V and 24V.
They come from MEDER, COTO, and others. Price maybe on the order of 20..50$, but your life is worth the price, I think.
Frank