Protection set

Main features

• Three phase measuring circuit
• Three definite-time overcurrent stages
• Ready to operate in one-, two- or three-phase power networks
• Measuring and continuous displaying of energising value
• Record of value of voltage during last disturbance
• Binary input in order block relay operation
• LED display and set of buttons in order to operation of the relay
• Optical indicating (with LED diodes) current voltage value (U<U1, U1<U<U2, U>U2), external blocking signal and proper operation of relay
• Relay output for signalling: II stage pick-up (K2), operation of I or II stage (K1), operation of III stage (K3) failure or lack of aux. voltage (K4) or relay interlock by external signal (K5)
• Self-test of proper operation of relay
• Relay enclosure gives possibility to mount on 35 mm rail, surface mount or flush mount

RIT-433A relay compares the maximum value of three measured currents with threshold values of particular overcurrent stages whose are set by the user. If the RMS value of any of measured currents exceed threshold value of one of overcurrent stages, relay picks-up and after set time, operates. Relay operation signal can be blocked by energising blocking purpose binary input (Ubl). Execution circuit is realised by three relay outputs: K1, K2, K3. Relay output K1 activates if I or II stage operate with adequate time-delay, relay output K2 is instantaneously activated by II stage pick-up, relay output K3 activates when III overcurrent stage operates after its time-delay expires.

TECHNICAL DATA