Gossen Metrawatt Metrahit 18S

Gossen Metrawatt Metrahit 18S

Status	supported
Source code	gmx_mh_1x_2x
Counts	31000
IEC 61010-1	CAT III 1000 V, CAT IV 600 V
Connectivity	Infrared (RS232)
Measurements	voltage, current, resistance, capacitance, temperature, diode, continuity
Features	autorange, data hold, bargraph

The Gossen Metrawatt Metrahit 18S is a 31000 counts handheld digital multimeter with IR (RS232) connectivity.

Hardware

• Battery: 9 V IEC 6 F 22 or IEC 6 LR 61 or corresponding rechargeable battery
• Fuse:
  • Current 300 mA: FF (UR) 1,6 A/500G; 6,3x32 mm
  • Current 3A, 10A:
    • Siba Ultrarapid 16A/600 V≈ 10mm x 38 mm
    • Littlefuse KLK 15A/600 V≈ 13/32” / 1 1/2”
    • Bussmann KLK 15A/600 V≈ 13/32” / 1 1/2”

• TODO.

Photos

• 

  Package

• 

  Inside

• 

  Display

• 

  IR Interface

Measurement functions and ranges

Measurement function	Range	Resolution	Accuracy	sigrok result	Remarks
V=	300 mV	10 μV	±(0,05% + 3)	mq V, unit V, mqflags DC
	3 V	100 μV	±(0,05% + 3)	"
	30 V	100 μV		"
	300 V	1 mV		"
	1000 V	10 mV		"
V≈	300 mV	10 µV	±(0,5% + 30) (> 500 Digit))	mq V, unit V, mqflags AC,RMS
	3 V	100 μV	±(0,5% + 30) (> 300 Digit)	"
	30 V	100 μV		"
	300 V	1 mV		"
	1000 V	10 mV		"
V≃	300 mV	10 μV	±(0,5% + 30) (> 500 Digit))	mq V, unit V, mqflags AC,DC,RMS
	3 V	100 μV	±(0,5% + 30) (> 300 Digit)	"
	30 V	100 μV		"
	300 V	1 mV		"
	1000 V	10 mV		"
V db≈	-48 - 63 dB	0,01 dB		mq V, unit V, mqflags AC,RMS	Actually 5 ranges.
V db≈ rel	-48 - 63 dB	0,01 dB		mq V, unit V, mqflags AC,RMS	Actually 5 ranges. To activate, press yellow button in dB mode, then do second measurement. Cannot be distinguished from non-rel measurement remotely.
A=	300.00 µA	100 nA		mq Curr., unit A, mqflags DC
	3.0000 mA	1 µA		"
	30.000 mA	1 µA		"
	300.00 mA	10 µA		"
	3.0000 A	100 µA		"
	10.000 A	1 mA		"
A≃	300.00 µA	100 nA		mq Curr., unit A, mqflags AC,DC,RMS
	3.0000 mA	1 µA		"
	30.000 mA	1 µA		"
	300.00 mA	10 µA		"
	3.0000 A	100 µA		"
	10.000 A	1 mA		"
Ω	300.00 Ω	10 mΩ		mq Res., unit Ω, mqflags -
	3.0000 kΩ	100 mΩ		"
	30.000 kΩ	1 Ω		"
	300.00 kΩ	10 Ω		"
	3.0000 MΩ	100 Ω		"
	30.000 MΩ	1 kΩ		"
Diode/Cont.	3.0000 V–	1 mV		mq V, unit V, mqflags DC,DIODE	Diode and cont. are identical on this device, just without beeper for diode.
Cap. F	3.000 nF	1 pF		mq Cap., unit F, mqflags -
	30.00 nF	10 pF		"
	300.0 nF	100 pF		"
	3.000 µF	1 nF		"
	30.00 µF	10 nF		"
	300.0 µF	100 nF	±(5.0% + 6)	"
	3.000 mF	1 µF		"
	10.00 mF	10 µF		"
Hz≃	300.00 Hz	0.01 Hz	±(0.1% + 3)	mq Freq., unit Hz, mqflags AC,DC
	3.0000 kHz	0.1 Hz		"
	30.000 kHz	1 Hz		"
	100.000 kHz	10 Hz		"
°C	Pt100 –200.0 - +100.0 °C	0.1 °C	2 Kelvin + 5	mq Temp., unit °C, mqflags -
	Pt100 +100.0 - +800.0 °C		±(1.0% + 5)	"
	Pt1000 –100.0 - +100.0 °C		2 Kelvin + 5	"
	Pt1000 +100.0 - +800.0 °C		±(1.0% + 5)	"
Event count				mq V, unit V, mqflags AC,RMS,REL	Counts events >= 2500 digits that last >=2s with a break >=2s. To activate, switch to voltage ACDC, press yellow button twice. Press up to 4 times to cycle parameters, press long to stop. See manual. Not useful remotely because the current measurement value is sent, not the counter.
Stop Watch				(Time data)	To activate, select a 3V-1000V range manually, press yellow button, press AUTO for start/stop, DATA for reset. Delivers only invalid data ("Overflow") via IR on  Matthias' device.
Data Hold				mqflags += HOLD	Disabled while IR interface is active on  Matthias' device.
MIN				mqflags += MIN	Influences only display, via IR flag is set, but actual current value is delivered.
MAX				mqflags += MAX	Influences only display, via IR flag is set, but actual current value is delivered.

The column "sigrok result" contains in short form what the driver generates for the resp. data type.