Pilz PNOZ XV3P safety relay

For cross short circuit detection (Rmax=10 Ω), the maximum length under the same wire diameter is ≈ 826m. If the on-site distance exceeds this value, the wire diameter needs to be increased or a relay needs to be used.

4.5 EMC and Wiring Points

The input, startup, and feedback loop cables should be routed separately from the power cables (frequency converters, motors, contactors), with a spacing of ≥ 200mm or using shielded cables.

Inductive loads (relays, contactor coils) must be equipped with suppression circuits at both ends of the contacts: RC absorption for AC and freewheeling diodes for DC (note diode polarity), otherwise it will seriously shorten the contact life.

It is not allowed to use the same contact for small currents (such as a few milliamps) after switching excessive currents, otherwise the signal may be unreliable due to increased contact resistance.

Delay configuration and startup mode setting

5.1 Adjustable Delay Setting (777510/777512/777518 and Spring Terminal Version)

The front panel has a knob engraved with multiple gears. Different gear types correspond to different delay values:

777510/787510 (0~30s gear): 0.1, 0.5, 1, 2, 4, 6, 8, 10, 15, 20, 25, 30 seconds.

777512/787512 (0-3s gear): 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 1, 1.5, 2, 3 seconds.

777518/787518 (0~300s gear): 0.3, 5, 10, 20, 40, 60, 80, 100, 150, 200, 250, 300 seconds.

Setting method: Use a small flathead screwdriver to rotate the knob to the desired scale. Attention: If the knob is located between two scales, the delay value may not be accurate. Is it strictly prohibited to rotate while powered on? The manual does not explicitly prohibit it, but it is recommended to set it after power failure.

Fixed delay models: 777514 (0.5s), 777517 (10s) without knob, internally fixed.

5.2 Startup Mode Configuration

Determine the startup mode through wiring:

Auto start: Short circuit S13 and S14 (which may have been short circuited at the factory). After the input circuit is closed, the unit will automatically activate the output after a delay of about 350-650ms (switch on delay).

Monitor start: Connect a normally open button (reset button) between S13 and S14. After the input circuit is closed, the button needs to be pressed for at least 30ms and must wait for 300ms (waiting period) after the input is closed before it can take effect. This can prevent unexpected restarts caused by input jitter.

Detection: In the monitored startup mode, if the reset button is not pressed after the input circuit is closed, the START LED will not light up and the safety contacts will not close.

Safety characteristic data and contact life

6.1 Security Level (from page 33 of the manual)

According to EN ISO 13849-1 and EN IEC 62061, the characteristics of PNOZ XV3P are as follows:

Operating mode PL Category SIL CL PFH_D [1/h] T-M [year]

Instantaneous safety contact PL e Cat.4 SIL 3 2.31E-09 20

Delay safety contact (TV<30s) PL d Cat. 3 SIL 3 2.64E-09 20

Delay safety contact (TV ≥ 30s) PL c Cat. 1 SIL 1 2.87E-09 20

Important: The longer the delay time, the lower the security level may be. When using a delay of more than 30 seconds, the risk should be reassessed (PL reduced to c). The above data is the contribution value of the module itself, and the overall safety function level needs to be calculated based on the basic unit and external wiring. It is recommended to use Pilz PAScal software.

6.2 Contact life diagram

The manual provides contact life curves for AC15 and DC13 loads (page 34). For example, under a 230V AC15 load and a switching current of 0.2A, the contact life is approximately 4 million times. The larger the current, the shorter the lifespan (such as about 100000 cycles at 5A).

Measures to extend lifespan:

Suppression circuits (RC/diodes) must be used for inductive loads.

If the expected lifespan caused by the actual switching frequency and load current is lower than the service life of the equipment, consideration should be given to using larger capacity contactors as intermediate amplifiers or using PZE expansion modules to share the current.

The manual states that if life curve data cannot be obtained, the given PFH value can be directly used for calculation, but it is only valid when the expected number of switches is lower than the corresponding value in the curve.

Common troubleshooting

7.1 Fault phenomenon: POWER LED lights up, but there is no output after closing the input circuit (START LED does not light up, contacts do not engage)

Possible reasons:

The startup circuit is not closed (S13-S14 open circuit and configured for monitored startup) or the automatic startup short circuit is missing.

Feedback loop Y39-Y40 is open (e.g. not short circuited or external expansion module failure).

Input circuit wiring error (mismatch between single/dual channel configuration and actual wiring).

The power supply voltage is below 20.4V.

Troubleshooting steps:

Measure the voltage of A1-A2, which should be ≥ 20.4V.

Check S13-S14: If it is an automatic start, the resistance should be measured to be approximately 0 Ω; If it is a monitored startup, it should conduct when the button is pressed.

Short circuit Y39-Y40 (temporary) test. If it returns to normal, check the external feedback contactor or PZE expansion module.