Pilz PSWZ X1P static monitoring

Input resistance: 1.3M Ω, which will not significantly affect the motor circuit.

Cable length limit: maximum total circuit resistance of 1.3M Ω, actual cable length=1.3M Ω/(cable resistance per kilometer). For example, if the resistance of a 1.5mm ² copper wire is about 13.7 Ω/km, the maximum length is about 95km (theoretical value, actual consideration of distributed capacitance and interference, it is recommended to control within 1000m).

Shielding requirement: When using a frequency converter, a shielded cable must be used to connect the PSWZ X1P to the motor, and the shielding layer must be grounded on the motor side.

4. Feedback loop (Y1-Y2)

It is necessary to connect the normally closed auxiliary contacts of the external contactor to form a feedback loop.

When the safety contact is disconnected, the external contactor should be disconnected accordingly, and its normally closed auxiliary contact should be closed, thereby closing the feedback loop. The PSWZ X1P will only allow the safety output to be re closed when the feedback loop is closed and both measurement channel voltages are below the response value.

If there is no external contactor (only used to directly cut off low-power loads), Y1-Y2 can be short circuited. But at this time, the monitoring function of the external contactor will be lost, and it is not recommended to use it for high safety levels.

5. Semiconductor output

Y32 (switch status output): High level (≈ 24V) indicates that the safety contact is closed.

Y35 (Fault Output): High level indicates a fault (such as synchronous timeout).

Both outputs require external 24V power supply (load capacity 50mA, short circuit protection). Cannot directly drive high-power loads.

6. Reset input (RESET)

The falling edge of the low level (<5V) after applying a high level (>15V) between terminal Y30 and the common terminal (0V) can reset the fault latch.

Commonly used for connecting external reset buttons or PLC outputs.

7. Fuse protection

A fuse must be installed before the safety contact (recommended: fast melting 6A, slow melting 4A, gG 6A, or C-characteristic circuit breaker 4A/24V).

Auxiliary contacts also need protection (with the same parameters).

Parameter Setting and Debugging

1. Adjustment of response threshold (Uon)

There is a potentiometer on the equipment panel used to set the response values of two channels simultaneously (the range depends on the model).

Factory default: Rotate counterclockwise to the bottom (minimum sensitivity).

Setup steps:

Ensure that the motor is in a completely stationary state (preferably just a few seconds after shutdown).

Rotate the potentiometer counterclockwise to the bottom, and the "CH.1 IN" and "CH.2 IN" LEDs should not light up (voltage below threshold).

Slowly rotate the potentiometer clockwise until these two LEDs just light up. The threshold set at this time is slightly higher than the current residual voltage of the motor.

Verification: Start the motor and then stop it, observe whether the LED lights up again after stopping. If restored, the settings are correct.

Suggestion: Seal the potentiometer with the provided label to prevent accidental adjustment.

Important warning: Static detection is only effective when the motor is powered off (the power circuit is completely disconnected) and there is no external excitation. If the frequency converter has not yet output inhibit, or if the motor is in position control mode (with excitation current still present), PSWZ X1P cannot detect stillness.

2. Release value (Uoff)

Fixed at twice the response value (Uoff=2 × Uon), with hysteresis characteristics. This ensures that the safety contacts are reliably disconnected when the voltage rises during the motor start-up process.

3. Simultaneous monitoring time (tg)

Maximum of 7 seconds. When the motor stops, the voltage of both channels must be lower than the response value within 7 seconds at the same time, otherwise the "FAULT" LED will be triggered and locked.

This time is not adjustable, but it is sufficient for most motors.

Application example: Static monitoring with star delta starter

The manual provides a typical application (see figure on page 15). This example demonstrates how to integrate PSWZ X1P in the star delta startup circuit.

Circuit composition:

SO: Emergency stop switch (off switch)

S1: Start button

S2/S4: Safety door switch (series)

S3: Release button (for confirmation before startup)

S5: Reset button (connected to RESET input)

K1: Star/Triangle Control Relay

K2: Main contactor

K3: Triangle contactor

K4: Star contactor

H: Fault indicator light (connected to auxiliary contacts 41-42)

Key wiring:

The safety contacts 13-14 and 23-24 of PSWZ X1P are connected in series to the control circuit of the main contactor K2.

The feedback loop Y1-Y2 is connected in series with the normally closed auxiliary contact of K2 (or multiple contactors are connected in series to ensure that the feedback loop is disconnected when any contactor is stuck).

The measurement input terminals L1, L2, and L3 are directly connected to the U, V, and W terminals of the motor (downstream of the contactor and not affected by contactor switching).