YOKOGAWA 2558

[kenramesh]

Hi,

need help / suggestion

 facing problem with yokogawa 2558 voltage current standard

display is not stable ,  seven segment led's -8 nos. (red ) flash ( 5 of voltage /current setting & 3 of % deviation) when unit is switched-on .
Flashing stops when the Range dial is rotated , reading dials rotated which cannot be relied.

sometimes the leds are stable but most of the time they go on flashing .

Even the OUTPUT ON/OFF switch, SWEEP switch automatically jump back to off position when the leds start flashing.

what could be the problem.

THANKS in advance

ramesh

[Zucca]

Open the device, take a DMM and make some measurement.
Post some pictures and more informations.

[coromonadalix]

Bad suply lines because of failed capacitors, buldged capacitors, bad contacts, bad solders   sure some photos would help,  for service manual, i haven't seen any Yokogawa material leaked ?? you can try to ask them