Process signals from external sensors need clean conversion, isolation and dependable power in one cabinet device. ST125M converts and isolates standard analog current and voltage signals and adds a transmitter power supply for external 2- and 3-wire sensors.
Selectable input and output ranges cover 0…20 mA, 4…20 mA, 0…10 V and 2…10 V. The 12.5 mm DIN rail housing keeps cabinet layouts compact, while the wide-range supply supports 20…125 V DC and 20…250 V AC. Front DIP switches set the signal type and live-zero range, with trimmers for \pm 2 % start and end value adjustment.
For reliable operation, microprocessor-controlled measurement recording detects underrange and overrange conditions and reports them via a two-color status LED. Selected Ex versions support intrinsically safe input and transmitter feed, and use in SIL2 systems according to EN 61508 is possible.
Front DIP switches configure current or voltage operation and live-zero ranges for the input and active analog output.
Two front trimmers adjust the starting value and end value of the measuring range by \pm 2 %.
ST125 versions provide an additional transmitter feed for external 2- and 3-wire sensors.
M versions use a wide-range supply for 20…125 V DC and 20…250 V AC. MP versions use 24 V DC via Power Rail.
The input signal is filtered, digitized with 14-bit resolution, scaled and transferred via an optocoupler to the output stage.
When a measuring range is undercut or exceeded, the output is set to a defined starting value or end value.
MP versions can be supplied through a mounting rail bus connector, with one bus adapter required for each device.
Ex versions are available with intrinsically safe input and transmitter feed for suitable hazardous-area sensor connections.
| Analog input type (voltage) |
0…10 V, 2…10V
|
|---|---|
| Analog input type (current) |
0…20 mA, 4…20 mA
|
| Operating relative humidity |
< 95 %RH
|
|---|---|
| Degree of protection front |
IP30
|
| Degree of protection terminals |
IP20
|
| Operating temperature |
-10...+60 °C
|
| Storage temperature |
-20...+80 °C
|
| Type of analog output |
0…20 mA, 4…20 mA,0…10 V, 2…10V
|
|---|---|
| Temperature coefficient |
0.01 %/K
|
| Accuracy |
0.2 %
|
| Burden (current output) |
< 600 Ω
|
| Dimensions |
12.5 mm x 108 mm x 114 mm
|
|---|---|
| Materials |
Polyamide (PA) 6.6, UL94V-0
|
| CE Conformity |
Yes
|
|---|---|
| ATEX marking |
II (1) G [Ex ia Ga] IIC, II (1) D [Ex ia Da] IIIC, II 3 G Ex ec [ic] IIB T4 Gc
|
| Electrical connection type |
Screw terminal box
|
|---|
| Auxiliary voltage |
20…125 V DC, 85…253 V AC, 24 V DC
|
|---|---|
| Power consumption |
< 4 VA, (2W for MP-Version)
|
| Protection class |
II
|
| Degree of pollution |
2
|
| Rated voltage |
300 V AC/DC
|
| Test voltage |
3 kV AC
|
| Internal Resistance (Ri) |
300 Ω
|
|---|---|
| Transmitter Power Supply |
> 15 V DC at 20 mA output current (terminals 51, 52); > 14 V DC at 20 mA output current (terminals 51, 41)
|
| Type of controls |
Poti, Dip-Switches
|
|---|
