PMA20 is an alternating or unidirectional continuous current monitoring relay, with maximum current tripping function. It has a universal auxiliary power supply manufacturer of 24…240VAC/DC. The current input can be connected through CT (Current transformer) or directly to a circuit to control.
At power on, the PMA20 conducts the inhibition time, set by rotary selector, during which the green LED flashes. At lapsing and with normal operating conditions referred to the set value, the green “ON” LED is then switched on constantly, the red LED is off and the output relay is in normal operating conditions (normally energised or de-energised based on the function selected). When the current value increases above or decreases below the set value, the red LED flashes. At the set delay time lapsing, the relay changes state and the red LED remains constantly on.
Resetting mode depends on the “Latch” function selected. With the relative potentiometer, the automatic device reset can be delayed after tripping. The delay is carried out in “Latch OFF” mode only.