Pilz PNOZ XV3P safety relay

Input circuit closed (e.g. emergency stop not pressed):

The internal relay is closed, and the instantaneous safety contacts 13-14, 23-24, and 33-34 are closed.

Delay contacts 47-48, 57-58 immediately close and start timing? No: The delay contact closes immediately when the input is closed and opens with a delay only when the input is disconnected. The manual clearly states: "Safety contacts 47-48 and 57-58 close when the input circuit is closed, and open after the delay time has expired when the input circuit is open." Correction: Delay contacts close immediately when the input is closed and only open after the input is disconnected via TV.

CH.1, CH.2, CH.1 [t], CH.2 [t] LEDs are all on. The START LED will turn off after the startup is completed.

Input circuit disconnected (press emergency stop):

Instantaneous contact opens immediately.

The delay contact remains closed to start the delay TV. After the TV ends, the delay contact opens and the CH.1 [t] and CH.2 [t] LEDs turn off.

Reset: To restart, the input circuit must be restored to closed, the delay time has ended, and the conditions for starting the circuit are met.

3.3 Special Function: Early Termination Delay

During the delay process, if the starting circuit (Y39-Y40) is disconnected, the delay can be terminated in advance and the delay contact can be immediately opened. This can be used for "canceling delay" in emergency situations. Just string a normally closed contact into the Y39-Y40 circuit.

Installation and wiring specifications

4.1 Mechanical Installation

Environmental temperature: -10 ℃~+55 ℃; Humidity 93% @ 40 ℃ without condensation.

Protection level: enclosure IP40, terminal IP20, installed in control cabinet (IP54).

Installation method: 35mm DIN rail, can be installed horizontally or vertically. Use the buckle on the back of the module to secure it.

Dimensions: Width 45mm, height 94mm (screw terminal) or 101mm (spring terminal), depth 121mm.

4.2 Power supply and input circuit wiring

Power supply: 24V DC, tolerance -15%/+10% (i.e. 20.4V~26.4V). Residual ripple ≤ 160% (≤ 38.4V peak). Power consumption of 4.5W. A power supply that complies with SELV/PELV standards must be used, and 0V must be grounded (to provide a ground fault detection reference).

Input circuit: Select the wiring method according to the safety level.

Wiring method: Terminal connection, maximum total cable resistance (Rmax), detection capability

Single channel S11-S12 short circuit, S21-S22 short circuit, using only one pair (such as S11-S21) 100 Ω ground fault

Dual channel no cross short circuit detection S11-S12 connected to one contact, S21-S22 connected to the other contact, no additional detection line 100 Ω ground fault or short circuit

The dual channel cross short circuit detection uses S11, S12, S21, S22, S31, S32 (see manual diagram for specific wiring), and requires additional connections of 10 Ω such as S22-S32 to detect cross short circuits between the two channels

Important: For wiring with cross short circuit detection, the maximum cable resistance is only 10 Ω. If the cable is too long, it may cause the fuse to fail to trigger within the specified time. The manual recommends performing the following tests after installation:

Keep the unit in working condition (with safety contacts closed).

Short circuit test terminals S22 and S32.

The internal fuse should activate within 2 minutes and the safety contacts should open.

Remove the short circuit and power off for about 1 minute to reset.

Start circuit:

Auto start: A jumper must be used to short circuit between S13 and S14.

Monitoring start: S13 is connected to the normally open button, S14 is connected to the other end of the button. The minimum width of the starting pulse is 30ms, and it must wait for 300ms after the input circuit is closed to effectively start (to avoid false triggering).

Feedback loop: Y39-Y40 should be connected in series with external contactors or normally closed auxiliary contacts of PZE expansion modules to confirm that the load has actually been disconnected. If no feedback is needed, Y39-Y40 must be short circuited.

4.3 Output contact fuse protection

To prevent contact welding, suitable fuses or circuit breakers must be connected in series in each output circuit. Recommended value:

Contact type: fast fuse, slow fuse, gG fuse, circuit breaker (B/C characteristics)

Instantaneous/Delay Safety Contact 10 A 6 A 10 A 6 A

Contact Capacity Comparison:

AC1 (resistive, 240V): maximum 8A, 2000VA

AC15 (inductive, 230V): maximum 5A

DC13 (inductive, 24V, 6 times/minute): maximum 7A

DC1 (resistive, 24V): maximum 8A, 200W

When multiple channels are loaded simultaneously, the total thermal current needs to be reduced. For example, using three contacts to conduct electricity simultaneously, the allowable thermal current for each contact is 5.5A (under 24V DC/AC1 conditions); Reduce to 4.3A using 5 contacts.

4.4 Cable length calculation

The maximum cable length is determined by the resistance limit:

Lmax=Rmax/(Rl/km)

For example, using a 1.5mm ² copper cable (with a resistance of approximately 12.1 Ω/km), the maximum length under a single channel of 100 Ω is approximately 8.26km (actually limited by distributed capacitance, but still far greater than typical on-site distances).