EOCR-PMZ (panel embedded) and EOCR-PFZ (embedded) motor comprehensive protector

Star delta starting wiring: ZCT must be installed above the main contactor (Main MC) and below the main circuit breaker (Main CB), that is, it must be bridged outside the delta switching area to avoid distortion of the current waveform during the starting process, which may cause misoperation.

4.3 4-20mA transmission output

The transmission output terminals+and - are used to connect PLCs or instruments. The output is active 4-20mA, isolated from the power supply. Set the current value in parameter 4-20 to correspond to a 20mA output (for example, if set to 150A, output 20mA at 150A, and output 4mA at 0A or below 0.5A). Shielded twisted pair cables (such as CVV-SB 2 × 1.25mm ²) must be used, with the shielding layer grounded at one end to prevent interference from sources such as frequency converters.

4.4 Fault Safety Mode (FS)

When the FS parameter is set to on, the relay's output contacts will switch to an alarm state (i.e. "fail safe") when the power is cut off or the self-test is abnormal. At this time, special attention should be paid: if the control power is taken from the main circuit of the motor, the change in contact state after power failure may cause misjudgment by the upper computer. It is recommended to set FS to on in important interlocking circuits and cooperate with UPS or independent control power supply.

Selection guide: Quickly locate the suitable model

5.1 Interpretation of EOCR-PMZ Order Code (Window Type)

Taking EOCR-PMZ-WRDZ7W as an example:

WR: Wide range of 0.5~60A (no need for external CT)

D: Output contact form (95-96 normally closed, 97-98 normally open)

Z7: Power supply AC/DC 85~250V, 50/60Hz

W: Hole Type

If an external CT is required, change the WR to H1 (100:5), HH (150:5), H2 (200:5), H3 (300:5), H4 (400:5), etc., and order the matching CT accessories separately.

5.2 EOCR-PFZ Ordering Code (Terminal Type)

Similar to the rule, the last T represents Terminal Type. For example, EOCR-PFZ-WRDZ7T is a wide range, 85-250V power supply, terminal type.

5.3 Attachment Selection

ZCT: Choose aperture sizes of 35mm, 80mm, or 120mm based on the outer diameter of the cable, such as ZCT-035.

Connecting cable: 15 pin flat cable, used for split installation (up to 10m in length), model such as CABLE-15-002 indicates 2 meters. When installing separately, the host can be installed on the cabinet door, and the CT unit can be placed inside the cabinet for easy inspection.

Fault diagnosis and reset: Quickly restore production

When EOCR trips, the panel will display fault codes (such as OC, UC, EC, RP, PL, etc.). Enter trip mode by pressing the up/down keys, and press SET to view in sequence:

Recent tripping reasons (such as OC)

L1, L2, L3 current values during tripping

Second and third trip records

Reset method:

Manual: Press the panel reset button.

Electrical: Disconnect the control power supply and then reconnect it.

Automatic: A-r needs to be set to the desired delay (0.3 seconds to 20 minutes) in advance. Attention: Automatic reset is invalid for faults such as reverse phase, phase loss, grounding, and locked rotor.

Common troubleshooting for false tripping:

Frequent OC tripping and actual current not exceeding: Check if the OC setting value is too low or if the OT delay is too short; For motors powered by frequency converters, high-order harmonics may cause false detections. You can try changing the action characteristics to In and increasing the delay appropriately.

EC (ground fault) misoperation: Check if ZCT is installed in the correct position (away from the output line of the frequency converter), and if the secondary line is damp or insulated; Temporarily set EC to OFF to confirm if it is external interference.

When powered on, RP (reverse phase) will be displayed: simply swap any two incoming lines to solve the problem.