How should modern equipment respond when current changes? A relay pair answers by offering help to engineers by setting the threshold and deciding how quickly the output current switches.
Prelta Systems offers the PS4395 and PS5395 current-sensing protective relays for this purpose. The PS4395 monitors AC current whereas the PS5395 is designed for bipolar DC current. Both relays can be configured with adjustable trip points and time delays, allowing engineers to set when an output should switch in response to a change in current.
The relays are used to monitor current flow in conductors. They have adjustable settings so that engineers can set the current level and the speed of the output change. If current rises above or goes below the set level then the output will change. This can be used to monitor equipment such as motors, pumps, fans and heaters.
The PS4395 can monitor AC currents between 1A and 100A with frequencies between 60Hz and 400Hz. The PS5395 can monitor bipolar DC currents in either range 1-10A, 3-30A, 6-60A or 10-100A. Both relays can also be set to have varying on delays of either 0.5-6 seconds, 2-25 seconds, 0.1-1 second or none which allows engineers to set how long it takes for the output to change.
The relays offer three output options, a 20A single-pole double-throw (SPDT) relay, an opto-isolated NPN transistor or an opto-isolated zero-crossing triac. The SPDT relay is rated for 20A normally open and 10A normally closed at 240V AC resistive load.
Both relays come with an internal current sensor with a half inch aperture. Remote transformers can be used if monitoring larger conductors.
For the official announcement, click here.
