An ebay find made its way into the lab- an industrial quality DMM from Hioki, made in 1984! The meter has some pretty good specs as shown in this datasheet:
- 3.5 digit (1999 count), 0.5% on DC voltage
- 20uA DC current range with 10nA resolution
- 1G input resistance on 200mV range
- Drop proof to 1 meter
- Dust sealed.
- 500 hours battery life using 2 AA
- Neon indicator of overvoltage
The meter came in an original case, that looked a bit beat up:
Case front
Case back
Probes with safety tips included
Safety shrouded probes
The case feels very solid with no play
Stand works pretty well
Original batteries. 2xAA is a bit unusual for the DMMs back then
1984 datcode!
The batteries held their voltage until I tried turning the meter on, then they sagged. Still remarkable condition and lack of leaks after almost 30 years
Back cover removed
Two non-arching fuses (HRC?). though the smaller one was blown
Spare fuse to the rescue
Attempting to insert modern AA batteries is met with a bit of resistance. They seem to have grown fatter over the last 30 years?
Quite a force is required to fit newer batteries in
Shielding cover removed
Shielding detail
More shielding details
Top of the board with back cover removed
No idea who made the chip
Binding posts are bolted to the board and loctited. Current shunt is in front
Attention to details
An interesting switch that gets pressed when the selector knob is in a particular position
Unfortunately,further board removal would require desoldering multiple leads and I was not about to do that to a functioning vintage meter. So let’s put it back together and try to turn it on:
Measuring one AA cell- clear and crisp display
1 Ohm
9 Mohm
5V DC reference
1mA DC current
To create low current, we’ll use a AA battery powering a large cap. Leakage should be pretty small:
Diode test- measures forward voltage and beeps rather loudly
Conclusion:
It’s a very impressive meter, especially considering the age. All functions appear to function with the exception of the AC voltage and current. It could be as simple as the mode button not making contact or could be more involved, but that’s a topic for another post.
An eevblog forum thread for this post could be used for comments
I bought one just like in 1985. is very good, but unfortunately 2 years ago I put 230v AC input by measuring ohms and broke., I’ve had it running for 22 years perfect
I have one since 1986 and has been my partner school and work throughout this time and still
works perfectly.
Hello
Does this HIOKI 3200 monovalent and sent to Taiwan USPS shipping how much money?
Hi,
The SCI9020F “chip” is probably Seiko-Epson corp.
I by mistake, connected HV across the pins of the output capacitor of a racket insect killer to the V measuring input , but after that it is defected & doesn’t measure OHMs properly.Model of multimeter is 3200 Hioki
Hi, i haven’t done any thing mistakenly but it doesn’t measure resistance too!!!
The model is 3200
What can i do now?
Help me!!!
This is my first digital multimeter, I bought in 1984, some years later I fall seduced by Fluke charming.
Still I have thos meter and work like new.
I have this since 1996 when i was 10 years old.very good multimeter.it works very well now. thanks to hioki
What’s it worth
I have worked with HIOKI 3200 years ago when I did electronics, I believe still they are the best after 35ysor more. perfect for precision works.
I have one . I bought in 1985 . it works excellent. how much is the price?
I have an old HIOKI 3200 Digital Hi Tester bought in 1984. It is now out of order as the LCD Display is not working. Can you provide some info where I can buy a spare part for the 13mm LCD Display.
I have an old hioki 3200 digitel multimeter.
Now the display is not working.can I get the display for the same
My mode btn broke as well. I soldered a new one to the board and all was good. Confirmed bad button by shorting the button pads with a screwdriver. The range button on mine is still broken, but who needs that anyway. lol
Hioki 3200-50 marked 1985
Anybody have the circuit diagram of Hioki 3200 multimeter some wire connections cut due to old and rust from board 3 wires red blue and going to where it connected. And battery +ve and -ve how many connections please anybody help me
I wont model no hioki 3200 only display if you have so please send me email Thanks
I have one since 1986 and it still works like its first day! I really love it.