Voltcraft VC-850

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Voltcraft VC-850
Status planned
Counts 6000
IEC 61010-1 CAT III (1000V) / CAT IV (600V)
Connectivity RS232 / USB
Measurements voltage, resistance, diode, continuity, capacitance, frequency, duty cycle, current, temperature
Features autorange, hold, relative, test-lead-detection (TLD), backlight
Website conrad.de

The Voltcraft VC-850 is a 6000 counts, CAT III (1000V) / CAT IV (600V) handheld digital multimeter with RS232 or USB connectivity.



  • Fortune Semiconductor FS9922-DMM4
  • ...

RS232 cable:

USB cable:




RS232 cable:

See Device cables#UNI-T_UT-D02.

USB cable:

See Device cables#UNI-T_UT-D04.


See Multimeter_ICs#Fortune_Semiconductor_FS9922-DMM4.

A short protocol description is also available from Voltcraft/Conrad.

This DMM is wired up a bit differently than "normal" for the diode mode, see below. The MEA5 to MEA1 bits are inputs of the FS9922-DMM4 chip, controlled by the position of the mode selection wheel on the DMM.

Mode (selection wheel) MEA5 MEA4 MEA3 MEA2 MEA1 Mode (FS9922-DMM4 datasheet)
Voltage DC / AC 1 0 0 0 1 DC / AC V (600.0mV ~ 6000V)
Capacitance 1 0 0 1 1 Capacitance
Resistance / continuity 0 1 1 0 0 Ohm / beeper
Diode 0 1 1 0 1 ADP (6.000)
Temperature (C / F) 1 1 1 1 1 C / F
Frequency / duty cycle 1 0 1 0 0 Hz / Duty
DC / AC current (µA) 1 1 0 1 1 DC / AC µA (600.0µA / 6000µA)
DC / AC current (mA) 1 1 1 0 1 DC / AC mA (60.00mA / 600.0mA)
DC / AC current (10A) 1 1 1 1 0 DC / AC A (6.000A / 60.00A)

When the mode selection wheel is turned to "diode" setting, the FS9922-DMM4 chip will not be put into one of its known "diode" modes ("Diode/Beeper", "Ohm/Diode/Beeper/cap.", or "Ohm/Beeper/Diode") but instead it will use the "ADP (6.000)" setting. This will light up COM4/SEG22 on the LCD (which is a "diode" symbol on this DMM) and in the PC protocol the "z1" user-defined bit will be set (but not the "voltage" and/or "diode" bits, as one would expect). Thus, some special handling is needed in order to properly parse the diode mode setting.

See the Fortune Semiconductor FS9922-DMM4 datasheet page 11 ("Measuring Modes Select") and 12 ("ADP Input/User-Defined Symbols and Confirmation of Decimal Locations") for details.