Description for Siemens 243-0048

The 243 Reverse Acting Relay provides a proportional output signal that varies inversely with the input signal. A spring adjustment is provided to allow setting a desired reverse acting schedule required by a particular application.Application: The 243 Reverse Acting Relay has two applications. For both, the supply air pressure must be equal to or greater than the spring setting. Signal Reverse Acting Relay Application: The relay reverses a controller signal to match the operation of a control element. An increase in input pressure causes equivalent decrease in output pressure. Signal Inverting Application: A typical application reverses the action of a face and bypass damper actuator on a coil used for both heating and cooling. The output pressure is directly proportional to the input pressure until one-half the spring setting is reached. After this point, the output pressure is inversely proportional to the input until the output reaches zero.Features:

Lightweight and compact Can be mounted in any position Mounting bracket and screws included Field adjustable spring range Can be used as a signal inverting relay Force-balance operation minimizes air consumption Internal relief provides fail-safe operation Amplifies air volume to minimize system lag