GW Instek GDM-397¶
GW Instek GDM-397¶
| Status | supported |
| Source code | serial-dmm |
| Counts | 4000 |
| IEC 61010-1 | CAT III (1000V) / CAT IV (600V) |
| Connectivity | RS232 |
| Measurements | voltage, current, resistance, capacitance, frequency, temperature, duty cycle, diode, continuity |
| Features | autorange, data hold, relative, backlight |
| Website | gwinstek.com |
The GW Instek GDM-397 is a 4000 count CAT III (1000V) / CAT IV (600V) handheld digital multimeter with RS232 connectivity.
It is similar to the UNI-T UT61B, but not the same device/PCB (this appears to have improvet input protection along with HRC fuses).
Press and hold the REL button to enable serial data transmission.
Hardware¶
Multimeter:
- Multimeter IC: Fortune Semiconductor FS9922-DMM3 (datasheet)
- Crystal: 4MHz (markings: "3.999")
- Fuses: 600mA H 1000V (6.35x31.8mm) and 10A H 1000V (10.3x38.1mm) (HRC fuses)
RS232 cable:
- Included (appears to be same as Device cables#UNI-T_UT-D02).
USB cable:
- Optional (appears to be same as Device cables#UNI-T_UT-D04).
Photos¶
Gdm 397 Rs232cable
Gdm 397 Front
Gdm 397 Pcb
Protocol¶
See Multimeter_ICs#Fortune_Semiconductor_FS9922-DMM3 for the DMM IC protocol. Depending on the cable, additional transport-specific decoding is needed, though.
Serial data transmission must be enabled by a long press on the "REL" button.