High Voltage Rectifier Metering

[bullit]

I need to upgrade voltage panel meters displaying DC voltage from the output of a high volt rectifier. The present meters are obsolete and use an input coming straight from the power supply. I think I need to install some kind of signal conditioner to display voltage from 0 to 800 DCV output using a modern DPM. Does anyone have any suggestions on where to start?

 

[Fish4Fun]

bullit,

Welcome to PF!

A lot depends on what type of accuracy you need, the physical parameters involved, the project budget and any safety codes that may be requisite.

First thing I would do is test if the existing Volt Meter is "scaled" internally, externally, or some combination of both. This should be easy enough to do, just measure the voltage on the leads run to the meter. If the voltage coming to the analog meter is in the mV range, then you will simply need a Digital Volt Meter (DVM) scaled to 0 to 2000V. If the voltage coming to the analog meter is full PS value (0-800Vdc) then you will need to devise a voltage divider to lower the voltage to a reasonable level. If the voltage coming to the analog meter is some scaled percentage of the PS value (perhaps 0-80Vdc) then you will likely be able to use a standard DVM with the appropriate scaling.

You will likely need a low voltage power supply for the DVM.

Fish

 

[bullit]

Thanks for your input. The voltage to the meter is full scale and I figured to have to use a voltage divider to get the signal down to a usable level. I am going to have to do some research to figure out what size resistors to use that will give me the correct scaling without building a fire on a board. Budget constraints are not much of an issue. These systems are broken and outdated and have to be fixed. I also need to get usable data scaled to feed I/O cards for a data collection system. By the way, what is excitation voltage referring to on a digital panel meter?