This bipolar limit detector module is designed to provide a relay contact transfer whenever the input signal exceeds one of the trip point settings. Separate relay outputs are supplied for the positive and negative setpoints. Once the contacts transfer, they will remain so until the input signal returns below the trigger threshold. Models are available for use with either voltage or current input signals. This module can be used in bidirectional applications to indicate a direction change or with double solenoid valves as a level controller. The differential input mode allows the module to transfer the relays based upon the absolute difference between two input signals of the same polarity.
This industrial grade module utilizes a stable reference to maintain the preset trip points within 1%, as the ambient temperature and power supply are varied over the specified operating range. The relay pickup point can be adjusted from 2% to 100% of the rated signal range. A small amount of hysteresis is included to prevent relay chatter due to noisy or slowly changing input signals.
Adjustment controls are included on the board to set both the positive and negative trip points as well as remove the offset from unipolar signals that do not go to zero. Visual indicators are provided to show the state of the output relays. Each output relay provides one form C contact. Provisions are included for either single ended or differential inputs This module requires a bipolar 10 to 30 volt DC power supply for operation.
The circuit board is solder masked. All external connections are made to a barrier type terminal block with #6-32 captive wire clamping screws. All external connections and controls are clearly marked. The board can be mounted in the user's control enclosure on standoffs or located in plastic mounting track.
Applications: Level controls, end of travel limit switch, depth control, velocity and position limit switches and general purpose bipolar , analog input signal limit indicator.