Gossen Metrawatt
Gossen Metrawatt is a German manufacturer of professional and high-end test and measurement equipment, including multimeters.
This article tries to give an overview of the multimeters with interfaces for data exchange, OEM models and communication.
Company
Multimeters
One remark concerning device names: The manufacturer writes the name of the device series sometimes "METRAHit", sometimes METRAHIT or even METRA HIT, sometimes not even consistently for the same device. For simplicity it will be "Metrahit" here most of the time, other names alike.
Metrahit 1x series
| Gossen Metrawatt | Siemens OEM | Rishabh | Count | TRMS | Supported | Remarks |
|---|---|---|---|---|---|---|
| Metrahit 12S (GTM 2012 000 R0003) | Rishmulti 12S | 3100 | ||||
| Metrahit 13S (GTM 2013 000 R0003) | Rishmulti 13S | 3100 | ||||
| Metrahit 14A (GTM 2014 000 R0007) | B1102 7KB1102-8AA | 3100 | ||||
| Metrahit 14S (GTM 2014 000 R0003) | B1103 7KB1103-8AA | Rishmulti 14S | 3100 | |||
| Metrahit 15S (GTM 2015 000 R0003) | Rishmulti 15S | 3100 | ||||
| Metrahit 16S (GTM 2016 000 R0003) | B1104 7KB1104-8AA | Rishmulti 16S | 3100 | ● | ||
| Metrahit 16I (M216B) | 3100 | ● | ● | Multimeter and insulation tester 500/1000 V | ||
| Metrahit 16L | 3100 | ● | Seems to be a Metrahit 16I with additional duty cycle function | |||
| Metrahit 16T (M216A) | 3100 | ● | Multimeter and insulation tester 100 V telecom | |||
| Metrahit 16U (M216U) | 3100 | ? | Multimeter and insulation tester for symmetrical copper wire, very similar to 16T | |||
| Metrahit 17 | B1107 7KB1107-8AA ? | 3100? | - | Milliohm meter (no IR interface, just listed for completeness) | ||
| Metrahit 18S (GTM 2018 000 R0003) | B1108 7KB1108-8AA | Rishmulti 18S | 31000 | ● | ● |
The Metrahit 1x series supports sending data via IR/RS232.
It seems that the 3100 count types are actually 31000 count types that do not display the last digit, but can deliver it via the serial interface.
The devices are not available from Gossen Metrawatt any more, but it seems that a company in India named Rishab makes slightly redesigned versions of them.
Currently the Metrahit 14A, 16I and 18S with interface RS232 are supported by sigrok using the driver gmc-mh-1x-2x-rs232. The other devices (except the 17, of course) should work theoretically, but are untested. Please contact Matthias if you have one of these devices and can test it.
Metrahit 2x Series
| Gossen Metrawatt | Siemens OEM | LEM ELMES/ HEME/NORMA OEM |
Dranetz brand | Count | TRMS | Remarks |
|---|---|---|---|---|---|---|
| Metrahit 22S (M222A) | 31000 | Signal Generator; Current measurement only with clamp | ||||
| Metrahit 22M (M222B) | 31000 | Signal Generator; Like 22S + Integrated measurement data storage | ||||
| Metrahit 23S (M223A) | 31000 | Signal Generator; special 16A (unfused) range for used with measuring current transformers | ||||
| Metrahit 24S (M224A) | 31000 | Signal Generator | ||||
| Metrahit 25S (M225A) | B1102 7KB1102-8BA | 31000 | AC | Signal Generator | ||
| Metrahit 26S (M226A) | 31000 | ● | Signal Generator | |||
| Metrahit 26M (M226B) | ● | Signal Generator; Like 26S + Integrated measurement data storage | ||||
| Metrahit 27EX (M227F) | Milliohm meter for explosive atmospheres | |||||
| Metrahit 27EX Airbus (M227G) | Milliohm meter for explosive atmospheres, special version approved by Airbus. | |||||
| Metrahit 27I (M227B) | B1107 B 7KB1107-8BA ? | DranTech PMIT | ● | Milliohm and Megaohm, insulation tester. Same device available as part of avionic kit 27AS (M227C). | ||
| Metrahit H+E Car (M227T) | ● | Special tester for Electro and Hybrid Cars. Milliohm and Megaohm, insulation tester. Seems to be a METRAHit 27I in different colors | ||||
| Metrahit 27M (M227A) | ● | Multimeter and Milliohmmeter | ||||
| Metrahit 28S (M228A) | B1105 7KB1105-8AA | Unigor 280 | 310000 | ● | ||
| Metrahit 28C (M231A) | 310000 | ● | Multimeter, Milliohmmeter + Calibrator | |||
| Metrahit 28C light (M232A) | (30000) | Calibrator; Only a signal generator, not a multimeter, added here just for completeness. | ||||
| Metrahit 29S (M229A) | B1106 7KB1106-8AA | Unigor 290 | PowerLogger 10 | 310000 | ● | Energy and power disturbance measurement functions, integrated memory. |
| Metrahit 30M (M230B) | DranTech ULTRA | 1200000 | ● | Laboratory multimeter; communication protocol not compatible with Metrahit 1x/2x devices! |
The Metrahit 2x series supports bidirectional data exchange via IR.
Currently the Metrahit 28S with unidirectional interface RS232 is supported by sigrok using the driver gmc-mh-1x-2x-rs232. The other devices will work probably, but are untested. Please contact Matthias if you have one of these devices and can test it.
Metrahit Starline Series
The series of newer devices with only three sockets (only one socket for all current measurement ranges) is called Starline Series. The manufacturer sub-divides this further into an A Series, E Series and S Series, which does not make a big difference concerning communicating with the devices.
| Gossen Metrawatt | Siemens OEM | Dranetz brand | Count | Remarks |
|---|---|---|---|---|
| Metrahit X-Tra (M240A) | Siemens B1125 7KB1125-8AA | Drantech XTRA | 12000 | Teardown on EEVblog: 1 |
| Metrahit Outdoor (M240o) | DranTech Outdoor | 12000 | IP65; seems to be a more rugged, different-coloured flavour of the X-Tra | |
| Seculife Hit (M687A) | 12000 | Seems to be a white, "medical" version of the X-Tra | ||
| Metrahit EBase (M251A) | 60000 | |||
| Metrahit ESpecial (M252A) | 60000 | |||
| Metrahit ETech (M253A) | 60000 | Simular to Extra, but fewer functions. | ||
| Metrahit Extra (M250A) | 60000 | |||
| Metrahit Energy (M249A) | 60000 | Energy and power analysis functions; EEVblog: Teardown: 1 Battery measurement: 2 | ||
| Metrahit Ultra (M248A) | 310000 | Precision Multimeter | ||
| Metrahit Ultra BT (M248B) | 310000 | Precision Multimeter with additional Bluetooth interface | ||
| Metrahit Iso (M246B) | DranTech ISO | 30000 | Multimeter with insulation measurement 50/100/250/500/1000 V, 3,1 GΩ | |
| Metrahit Iso Aero (M246M) | 30000 | Multimeter with insulation measurement 10/50/100/250/500/1000 V, 3,1 GΩ | ||
| Metrahit T-Com (M246A) | 3100 | Multimeter with special functions for symmetrical copper wiring, insulation measurement 100V | ||
| Metrahit T-Com Plus (M246S) | 3100 | Like T-Com, some more functions. | ||
| Metracal MC (M245A) | 60000 | Multimeter and calibrator; older versions named Metrahit Multical. |
Metraport Series
| Gossen Metrawatt | Volkswagen OEM | Count | Remarks |
|---|---|---|---|
| Metraport 40S (M234D) | V.A.G 1526E | 30000 | Foldable multimeter; USB interface, resettable fuse |
Communication Hardware
Most Gossen Metrawatt multimeters having data communication support communicate unidirectionally or bi-directionally through the case using IR and proprietary communication adaptors. The advantage of this construction is that it allows a closed case without unnecessary holes (one model, the Metrahit Outdoor, even has IP65 protection!), the disadvantage is a need for special, expensive adaptors to convert this to common RS232 or USB. Please note that the IR is just serial data (?), not IrDA.
The Metrahit Ultra BT also supports Bluetooth.
Metrahit 1x/2x series
Metrahit RS232
IR→RS232 adaptor for unidirectional communication from the multimeter to the computer.
Works with Metrahit 1x and with Metrahit 2x devices in Send Mode.
RS232 parameters: 8192 (Metrahit 1x)/9600 Baud (Metrahit 2x), 6N1, DTR ON, RTS ON.
The communication speed of 8192 Baud might not be supported by some operating systems and RS232-USB adaptors.
Not available any more.
RS232 IR→RS232 adaptor
With counterpart Metrahit 18S
Attached to Metrahit 18S
The adaptor contains just discrete components and ICs, no microcontroller.
Metrahit SI232
IR→RS232 adaptor for unidirectional communication from the multimeter to the computer and data storage.
Works with Metrahit 1x and with Metrahit 2x devices in Send Mode.
Up to six SI232 can be cascaded to communicate to the computer via a single RS232 interface. Up to 10 SI232 can be cascaded to measure offline synchronously.
128 kByte battery-buffered CMOS memory, up to about 100000 data sets.
Multimeter: 8192 Baud, 950 nm, 6N1 (?).
RS232: 9600/19200/38400 Baud, 8N1.
Not available from Gossen Metrawatt any more. It seems that Rishab in India 1 still sells it as OEM product Rish SI232.
Metrahit BD232
IR↔RS232 adaptor allowing bidirectional communication between multimeter and computer.
Works with Metrahit 2x devices, including 30M.
Up to six BD232 can be cascaded to communicate to the computer via a single RS232 interface. When only Metrahit 2x multimeters are used, BD232 and SI232 adaptors can be mixed.
9600/19200/38400 Baud.
Matthias' experience is that this adaptor works as a replacement for a Metrahit RS232 with Metrahit 1x devices on some RS232 ports, but not on others.
Left side
Right side
Inside
Board bottom
Board top
The adaptor contains just discrete components and ICs, no microcontroller.
Metrahit SI232 II
IR↔RS232 adaptor allowing bidirectional communication between multimeter and computer and data storage.
Works with Metrahit 1x and Metrahit 2x devices.
128 kByte battery-buffered CMOS memory, up to about 100000 data sets.
Multimeter: 8192/9600 Baud, 950 nm, 8N1.
RS232: 9600/19200/38400 Baud, 8N1.
4-8 SI232 II (depending on multimeter types and baud rate) can be cascaded to communicate to the computer via a single RS232 interface. Up to 10 SI232 II can be cascaded to measure offline synchronously.
Not available any more.
USB-Hit
IR↔USB adaptor for Metrahit.
For Metrahit 2x/30M devices only.
Metrahit Starline Series
USB X-Tra
IR↔USB adaptor for the Starline Series devices.
Bluetooth
Bluetooth 2.1 + EDR, Class 2
For the Metrahit Ultra BT.
Communication Protocols
While the older devices MetraHit 1x-30M use proprietary protocols, the newer devices of the socalled Starline Series use a protocol close to SCPI. Descriptions of the communication protocols are available from the manufacturer.
Metrahit 1x/2x Send Mode
Proprietary binary protocol. Used for sending data to PC.
Metrahit 1x/2x Block Send Mode
Proprietary binary protocol. Used for polling buffered data from PC.
Metrahit 2x Other modes
There seem to be 2 or 3 other communication modes for the Metrahit 2x series. See description available from manufacturer.
Metrahit 30M
The protocol is proprietary and seems to be quite different from the Metrahit 1x/2x series although communication can use some of the same IR↔RS232 adaptors (at least BD232, USB-Hit).
Starline Series, Metraport 40S
Newer Metrahit devices use a proprietary communication protocol that is basically SCPI with an escape mechanism for some special chars.
LabView
Gossen Metrawatt offers LabView drivers for the Metrahit Energy, the Metrahit Ultra and the Metraport 40S.