Electronics > Repair

Hioki RM3545 Resistance Meter Repair

(1/2) > >>

Kosmic:
Hello,

I have a Hioki RM3545 here that suffered what appear to be an overload on the input. I initially found a blown resistor R3010 (100Ohm?) and it was replaced. Now the instrument seem to work OK on the lower ranges.

Unfortunately on the higher ranges it read low. After investigating, 2 more blown resistors were found R341 and R370. I have no idea of their values though. Anybody with a RM3545 could measure R341 and R370 for me ?

PS: I already sent an email to Hioki and they answered me it’s not a good idea to do board repair  ::)

Thanks!



HighVoltage:
Interesting project, bookmarked.

I repaired a Hioki DMM once and they were also not very helpful at all.
Hopefully you find someone with such an instrument.

coromonadalix:
since 1 side of them are connected together ???

this is not an item we see often here,  you may wait a long time,  i would try to find where the traces goes and see if it could be some range  parts

Kosmic:
Look like it's part of some kind of feedback circuit connected to Sense+ (on the input). The resistors are after some protection diodes and they all goes to an analog switch (DG441).



Interestingly if I just remove the diodes (disconnect everything) the instrument is working as expected. I would still like to have that protection circuit in place.

gamalot:
I just opened my RM3545 and measured those resistors with a multimeter and LCR. The results are in the attached picture.

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod