The DT1400 … Limit switches compare the 0-20 mA / 4-20 mA / 0-10 V / 2-10 V / 0-5 V output signal with the set values.
When the output signal exceed one of the set values the instrument activates the corresponding SPDT relay contact.
The DT1400 … Limit switch is also a process indicator and enable linear process variable to be displayed in engineering unit on its 5 digit LED display.
The instrument is available with the following output options (2 limit-relays are standard, beyond that only one option at the same time):
- +2 normally open relay contacts (SPST) for limit switching or for simple control tasks. (In this case 4 limit-relay contacts are in the DT1400.)
- 0-20 mA / 4-20 mA galvanic isolated, scalable, active or passive current output.
- 15 VDC, 30 mA, galvanic isolated power supply for two wire 4-20 mA transmitter.
The functional parameters can be set by push-buttons on the front panel of the device, through a simple menu system: input selection, averaging of input signals, scaling, display frequency, limit values, limit operating modes, histeresis, scaling the analogue output, etc. The settings are protected by a two-level password against unauthorised manipulation.
The DT1400 … has two power supply versions:
- 18-40 V DC / 14-29 V AC (DT1400 …)
- 140-250 V AC / 180-250 V DC (DT1400 … PS).