It is twice as noisy as the 7510...
Since the warranty has expired on my DM7276-01, and if there is any interest, I could open it up and take some pictures from the inside.
In this picture the Hioki DM7276 was hooked up to my LTZ1000A reference over night
Settings:
- 100 NPLC
- Smoothing filter ON with 5 average readings
The nominal value of my LTZ1000 reference is 7.065,90xV
For comparison I had the Keithley DMM7510 running in parallel to the Hioki.
Thanks for the tests and teardown. Something seems wrong with Hioki displayed statistics. P-P cannot be less than twice S_n. P_P would be equal to twice S_n if the distribution is purely bimodal, otherwise P_P should be more than twice S_n.
While Keysight 34470A and keithley DMM7510 had a dramatic price increased in the last few years, this Hioki Voltmeter has been stable.
Since the warranty has expired on my DM7276-01, and if there is any interest, I could open it up and take some pictures from the inside.
While Keysight 34470A and keithley DMM7510 had a dramatic price increased in the last few years, this Hioki Voltmeter has been stable.
Since the warranty has expired on my DM7276-01, and if there is any interest, I could open it up and take some pictures from the inside.
I like Hioki products, but for home user their products are not too much interesting. When the products are out of the support, they do not calibrate the device nor send the calibration/service manual (same experience with Japan and Czech support). Compared to mentioned Keysight or Keithley, where the calibration adjustment procedure is available.
Sorry to go off topic again, are these resistor values 1.58K? I have never seen such top marking before.
Sorry to go off topic again, are these resistor values 1.58K? I have never seen such top marking before.
1.58 kohm is correct, these resistors are likely made by KOA.
If anyone is interested, I've made a DIY temperature probe for Hioki DM7275, DM7276 & RM3544.
The build is documented on https://lajtronix.eu/2024/02/21/diy-hioki-dm7275-76-temp-probe-z2001/
It has been tested and is working great.
Br, Lajt
I have a question though - does anybody knows a calibration company in the UK which would calibrate this unit with traceability, data and uncertainties (to my surprise, the unit came without any calibration data from the manufacturer).
I'm a bit surprised there is no linearity check like a negative voltage or say 50% of range in the calibration procedure. I didn't study the design, but is the linearity guaranteed by design?