Pilz PDP67 F 4 code module safety installation and fault diagnosis guide

In industrial automation sites, the safe and reliable transmission of safety signals is the core of ensuring the safety of equipment and personnel. When old security distributed modules (such as some discontinued models) fail or high protection level security input/output nodes need to be configured for new devices, the Pilz PDP67 F 4 code series modules (including standard and VA types) provide a passive allocation solution for IP67 protection level. This article is aimed at on-site engineers, combining the hardware structure, wiring rules, serial applications, and typical troubleshooting of the module to help you quickly grasp the deployment and maintenance points of the module.

Product positioning and applicable scenarios

The Pilz PDP67 F 4 code module (order number 773603) and its stainless steel nut version PDP67 F 4 code VA (order number 773613) are a decentralized passive distributor. Its design goal is to centrally connect Pilz's PSENcode, PSENslock, PSENini and other safety sensors to Pilz safety assessment equipment (such as PNOZmulti or PSS series) in harsh industrial environments (humidity, dust, large temperature changes).

Typical applications include:

Safety door monitoring of robot workstation (multiple PSENslock locking devices connected in series)

Position detection on the conveyor line (multiple PSENcode encoded safety sensors)

Outdoor or flushing environment equipment that requires IP67 protection level

Compared to traditional IP20 junction boxes, this module directly uses M12 circular connectors without the need for additional control cabinets, significantly reducing wiring costs and improving system anti-interference capabilities.

Hardware Structure and Core Features

1. Interface distribution

The front of the module provides:

X1~X4: 4 8-pin M12 female sockets for connecting safety sensors

X5: 8-pin M12 female socket, connected to the safety input of the evaluation device (dual channel signal)

X6:8-pin M12 female socket, connected to standard I/O of evaluation equipment or controller, used for diagnostic signals (Diag) and lock control commands (Lock)

LED indicator lights: Power (green), Diag (green), Lock (green)

2. Electrical characteristics

Supply voltage: 24 V DC (allowable fluctuation see technical parameters)

Maximum carrying current per module: 2 A (UB end)

Working temperature range: -40 ° C to+60 ° C

Protection level: Overall IP67 (unused interfaces must be properly sealed)

3. Mechanical characteristics

Shell material: PBT (polybutylene terephthalate) or stainless steel version

Installation method: fix 2 M4 screws on a flat surface

Size: 120mm x 60mm x 20mm, weight approximately 240g

These features allow modules to be directly installed on equipment frames or machine bodies without the need for separate protective enclosures.

Safe use and compliance requirements

1. Expected use and limitations

The module is only allowed to connect to the safety sensor series specified by Pilz (PSENcode, PSENslock, PSENini) and cooperate with Pilz evaluation equipment. Prohibit the following behaviors:

Perform any soldering or component replacement on the circuit board

Use beyond the voltage, current, and temperature range specified in the technical parameters

Drive the actuator directly without connecting the evaluation device

2. Personnel qualifications

Installation, wiring, debugging, and troubleshooting must be completed by qualified personnel with safety technical knowledge. Specific requirements include:

Familiar with basic laws and regulations for accident prevention

Understand the safety warning content in this manual

Master relevant product standards (such as EN ISO 13849, IEC 62061)

3. Disposal requirements

When scrapping products, it is necessary to comply with local electronic waste disposal regulations (such as the EU WEEE Directive). The shell material is recyclable, and the internal circuit board must not be mixed with household waste.

Mechanical Installation Guide

1. Installation steps

Process two M4 internal threads on the installation surface, with the hole spacing referring to the installation groove on the back of the module (the spacing is not fixed, subject to the actual slot).

Use M4 screws (recommended length 10-12 mm) to secure the module, with a tightening torque of approximately 0.6 N · m.

Ensure that the installation plane is flat to avoid deformation of the shell causing seal failure.

All unused M12 female sockets must be sealed with the accompanying blind plugs, otherwise IP67 cannot be guaranteed.

2. Space precautions

Considering the bending radius of M12 plugs and cables (usually 5-10 times the wire diameter), sufficient spacing should be reserved between modules and surrounding devices.

If multiple modules are connected in series, it is recommended to use the adapter PDP67 Connector cs (order number 773610 or 773612) provided by Pilz to reduce the connection failure rate.

Detailed wiring rules

1. Pin allocation of connectors (X1~X4)

Definition and Explanation of Pin Signal

Input I2 (S21) safety sensor channel B (normally closed contact)

2 24 V DC (A1) sensor power supply positive pole

Output O1 (12) safety signal to X5

4 outputs O2 (22) safety signal output to X5 (redundant channel)

Diagnostic output Diag (Y32) sensor status signal (non safety)

6 inputs I1 (S11) safety sensor channel A

7 0 V (A2) sensor power supply negative pole

Lock (S31) is an electromagnetic lock control command used for PSENslock

Engineering Tip: For PSENcode encoded sensors, only use pins 1/3/4/6; For PSENslock, pins 8 and 5 (Diag optional) need to be connected.

2. X5 connection evaluation device security input

Pin signal description

1. Connect I2 to the safety input channel of the evaluation device. 2

2 24 V DC (UB) module power supply positive pole (from evaluation equipment or external power source)

6 inputs I1 connected to evaluation device security input channel 1

7 0 V (UB) power supply negative pole

The remaining pins (3, 4, 5, 8) are idle (n.c.).

3. X6 connects standard I/O and lock control

Purpose of Pin Signal

Diagnostic status of X1 sensor corresponding to Diag 1

2 Diag 2 corresponds to X2

3 Diag 3 corresponds to X3

4 Diag 4 corresponds to X4

5 Lock 1 controls the magnetic locking of X1 sensor

6 Lock 2 Control X2

7 Lock 3 Control X3

8 Lock 4 Control X4

Important: The Diag signal is a non safety output and is only used for status indication or PLC monitoring. It should not be used for safety functions.

Independent circuit and series connection operation

1. Independent circuit (for single module use)

Connect 1-4 sensors to X1 → X4 in sequence, and the evaluation device must be connected to the last available mother socket (for example, if X1/X2 sensors are connected, X3 or X4 must be occupied by the evaluation device); If only X1 is used, the evaluation device can be connected to any of X2~X5, but it must be ensured that it is the interface that was not connected to the sensor at the end.

Typical error: If the evaluation device is connected to X2 and X3 also has a sensor, the sensor signal of X3 will not be recognized by the evaluation device, resulting in complete failure of the safety function. The manual clearly emphasizes this risk in the form of a warning.

2. Module series connection (extended to 8 or more sensors)

Multiple PDP67 F4 code modules can be connected in series through the adapter PDP67 Connector cs:

The last available female socket (such as X5) of the first module is connected to X1 of the second module.

The maximum number of series connections is limited by the supply voltage drop and total current (up to 2A per module).

It is necessary to ensure that the power supply voltage of the end module is not lower than the minimum allowable value of the sensor and module (usually 24V -10%=21.6V).

3. Voltage drop calculation method

When wiring long-distance on site, voltage drop may cause sensor undervoltage reset or misoperation. Calculation formula:

ΔU=Itotal×Rcable×L

ΔU=I total×R cable×L

among which

Itotal total=total current of all modules and sensors (A)

Rcable=resistance per unit length of cable (Ω/m)

L=cable length (m)

Reference data (provided by Pilz):

0.25 mm ² sensor cable: 0.15 V drop per 10 m and per 100 mA current

0.34 mm ² cable: 0.11 V/(10m · 100mA)

0.5 mm ² cable: 0.07 V/(10m · 100mA)

Example: Using 0.25 mm ² cable, length 50 m, total current 1.2 A.

Every 10 meters of voltage drop=0.15 V × (1200 mA/100 mA)=1.8 V.

50 m total voltage drop=1.8 V × 5=9 V.

If the starting voltage is 24 V and the end voltage is only 15 V, it is much lower than the minimum operating voltage.

Countermeasure: Increase the wire diameter, reduce the length, or increase the starting voltage (but not exceeding 26.4 V).

Debugging and Status Diagnosis

1. Meaning of LED indicator lights

Meaning of LED status

The power supply of the Power module is normally on

Extinguish without power supply or internal insurance (if any) damaged

The Diag constant light corresponds to the actuator of the sensor being within the response range (such as the encoder sensing in place)

The extinguishing actuator is not within the response range, or the sensor is not connected

Lock constantly on. Received magnetic lock control command (high level)

Extinguish unlock command or lock release

Note: Diag and Lock LEDs correspond to the currently activated sensors, but the manual does not specify which LED corresponds to which channel. In practice, the mapping relationship needs to be determined by triggering a single sensor to observe LED changes.

2. Power on self-test process

Connect the 24V power supply, the Power LED must be constantly on.

Trigger each safety sensor one by one (such as opening the safety door, moving the encoder execution block), observe and evaluate whether the corresponding input of the device flips.

Check and evaluate whether the safety output of the equipment follows logical actions (such as contactor disconnection).

For PSENslock, send a separate Lock unlock command and confirm the Lock LED and electromagnet sound.

3. Common fault phenomena and troubleshooting

Possible causes and solutions for the fault phenomenon

The power LED does not light up. If the power supply is disconnected, short circuited, or the module is damaged internally, the voltage at pins 2-7 of X5 should be 24V. Check the power capacity

Diag LED is always on, but there is no signal from the evaluation device. Safety signal line (O1/O2) has poor contact. Check X5 pin 1/6 wiring and evaluate device configuration

A single sensor has no response and is not connected in sequence (skipping X2 and directly connecting X3). All sensors must be continuously occupied from X1 onwards

The unstable operation of the serial end module results in a significant voltage drop. Calculate according to the above formula and reduce the length of the wire or thicken the cable

Lock LED has no response. Lock control signal is not correctly connected to X6 or the voltage is insufficient. Check if the corresponding pin of X6 has 24V and if the common terminal is connected correctly

Engineering Proposal for Replacing Old Distributed I/O Modules

For the outdated solution of using non safety IP20 remote I/O and safety relay combination on site, PDP67 F 4 code combined with PSENcode sensor can provide higher diagnostic coverage and simpler wiring. Attention when replacing:

Evaluate the original safety circuit: Confirm the stopping category (0 or 1) of the original system. PSENcode sensors usually support OSSD output and can be directly connected to I1/I2 of PDP67.

Update evaluation equipment configuration: If the original evaluation equipment is not from the Pilz brand, it is necessary to verify whether its safety input is compatible with the "dual channel 24V pulse test". The PDP67 module is a purely passive allocation that does not alter signal characteristics, but requires the evaluation equipment to be able to handle capacitive loads from long cables.

Mechanical adaptation: If the original system uses M8 or 7/8 "connectors, it is necessary to purchase conversion cables or replace sensors (it is recommended to directly use Pilz M12 pre cast cables, please refer to the manual attachment for the order number).

Verification response time: Connecting modules in series will increase the interruption delay (approximately 10-20 ms for each sensor), and it is necessary to ensure that the total delay meets the safety distance calculation.

Maintenance and Periodic Inspection

Even if the module itself has no moving parts, the following maintenance items cannot be ignored:

Every 6 months: Check if all M12 plugs are tightened, if blind plugs are missing, and if the sealing rings are aging.

Every year: Use functional testing tools (such as Pilz handheld testers) to verify whether the safety output of each sensor can be correctly cut off.

Environmental adaptability: If the module is exposed to cutting fluid or corrosive gases, VA type (stainless steel nuts) have better corrosion resistance.

Firmware/Document Update: Although the module does not have firmware, regular visits to the Pilz official website (www.pilz. com) should be made to confirm if there are any new application guides or warning notifications.