Difference between revisions of "Norma DM950"
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The ''printer cable'' has got a power connector (10-16 V DC, 50 mA) to power the multimeter and the interface externally. | The ''printer cable'' has got a power connector (10-16 V DC, 50 mA) to power the multimeter and the interface externally. | ||
The interface board is based on a NEC 75P116 microcontroller. | |||
= Photos = | = Photos = |
Revision as of 10:59, 4 October 2013
The LEM Norma DM9x0 Series of multimeters are 21000 count CAT II/CAT III hand multimeters with optional RS232 connectivity. The models differ by precision and feature set.
They were also sold as OEM devices by Siemens.
The manufacturer was a company named Norma, later LEM Norma in Austria.
Models
Model | Siemens OEM | Precision (DC) | Backlight | RMS | TRMS | R 20 MΩ | R 200 MΩ | U AC 1 kΩ/V | I 10A | f | C |
---|---|---|---|---|---|---|---|---|---|---|---|
Norma DM910 | B1024 | ±(0.5% +2d) | ● | ● | |||||||
Norma DM920 | B1025 | ±(0.5% +2d) | ● | ● | ● | ||||||
Norma DM930 | B1026 | ±(0.3% +3d/+2d) | ● | ● | ● | ● | ● | ● | ● | ||
Norma DM940 | B1027 | ±(0.1% +3d/+2d) | ● | ● | ● | ● | ● | ● | ● | ||
Norma DM950 | B1028 | ±(0.06% +3d/+2d) | ● | ● | ● | ● | ● | ● | ● | ● |
The RS232 interface is optional. All models were available with or without RS232 interface, the RS232 interface was also available as an accessory.
Hardware
Multimeter
Interface
The RS232 interface consists of the following components:
- Interface board (installed inside of multimeter)
- Printer cable 5-pin to DB9
- PC adaptor (Null modem plug with slightly unusal pinout)
The RS232 interface is designed to allow a direct connection to a serial printer or data recorder. Therefore an adaptor is required to connect it to a PC.
Comm parameters (PC): DTR on, RTS off, RTS/CTS flow control (!).
If the interface cannot be powered from RS232 (e. g. RS232-USB converter with too low voltage), switching on the multimeter with the FUNC button pressed powers the interface from multimeter.
The printer cable has got a power connector (10-16 V DC, 50 mA) to power the multimeter and the interface externally.
The interface board is based on a NEC 75P116 microcontroller.
Photos
Multimeter:
RS232 cable:
Protocol
Printer Mode
TODO
PC communication mode
TODO