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Products => Test Equipment => Topic started by: CookieMonster on December 30, 2021, 01:20:06 pm

Title: Rigol DP832 - Shows current with no load attached ?!
Post by: CookieMonster on December 30, 2021, 01:20:06 pm

Hi Guys,

I've been using my Rigol DP832 PSU for about 4 years without any problems.
As I turned it on yesterday, it was showing a current even with no load attached.

This is true for channel 1 and 2, not for the 3rd one.
The current is always 0,001A or 0,002A but can jump up to 0.005A when the voltage is changed while the output is enabled.
Apart from that, the PSU seems to operate correctly and does show current correctly when a load is attached.

I have never seen this behaviour before.

Any ideas ?

Thanks !

Title: Re: Rigol DP832 - Shows current with no load attached ?!
Post by: H.O on December 30, 2021, 02:30:00 pm

Seems fine to me.
The specification for current readback says 0.15%+5mA so at an actual current of 0 it still (just) meets its 12 months accuracy spec - after 4 years.

There's capacitance across the output of the power supply. When you change the voltage (with the output enabled) current will flow thru that capacitance in order to charge it to the new voltage.

If the tiny offset REALLY bothers you it is possible to calibrate.

(FWIW, mine shows 0.001A without any load connected.)