Pump protection relay with phase failure protection and underload restart timer function – 400V
The PPR is designed for use on motors which require sensitive overload and underload protection and is particularly suitable for offering good protection on borehole and pump set motors
The PPR offers phase failure protection which is voltage or current dependent. On power up all 3 phases must be present and connected in the following manner. L1 is used for the PPR ON/OFF control energising the unit on terminal 2. L2 connects to terminal 8. L3 connects to terminal 10. On single phase units, terminal 10 is connected to Neutral. During running the phase failure protection is dependent on the current transformer and if the PPR is set correctly, it will respond extremely fast. Both overload and underload have Set/Trip point LEDs with a common adjustable 0-10 second trip delay timer. There is fixed start-up delay of 5 seconds. A 50/5 CT, with a option of 3 connections (turns through CT), and 1 & 5 amp DIP switch selection provides various settings for motors 0.37kW to 7.5kW. For larger motors any size ring CT with a 5 amp secondary can b be used
The PPR is fitted with a underload re-start timer controlled by 4 DIP switches offering 6 time settings from 20 minutes to 8 hours (for borehole recovery)
If the installation is fitted with a discharge valve and ammeter, the over and under setting combinations are numerous with loads very easy to simulate