Pilz PSEN opII4H Safety Light Curtain Complete Guide

2.3 Dead zone processing

When using the standard installation kit, there will be a 15.4mm dead zone on both sides of the safety light curtain (objects cannot be detected within the dead zone). For applications that require no dead zone installation, the PSEN opII Adv Bracket Kit extension installation kit should be used. This kit provides multiple clamping units, which can be selected from 2 (150-600mm), 3 (750-1200mm), or 4 (1350-1800mm) clamping units according to the protection height, achieving installation without dead zones on both sides.

3. Calculation of safety distance

3.1 The Importance of Safe Distance

The safety distance refers to the minimum distance between the protection area of the safety light curtain and the hazard source. The setting of this distance must ensure that the operator cannot reach the dangerous area before the dangerous movement stops. The calculation of safety distance is based on the EN ISO 13855 standard, and the calculation formula is as follows:

S = K × (t₁ + t₂) + C

among which

S: Minimum safe distance (mm)

K: Approaching speed, take 1600mm/s when S>500mm, and 2000mm/s when S ≤ 500mm

T ₁: Response time of safety light curtain (s)

T ₂: Stop time of the machine (s)

C: Additional distance, set at 128mm for hand protection

3.2 Factors affecting response time

It is worth noting that when using the beam encoding function, the response time of the safety light curtain will increase. The specific values vary depending on the protection height:

300mm protection height: no coding response time 11.7ms, coding response time 15.2ms

900mm protection height: no coding response time 8.4ms, coding response time 22.3ms

1800mm protection height: no coding response time 12.3ms, coding response time 22.3ms

Therefore, when planning the safe distance, it is necessary to calculate the corresponding response time based on the actual coding mode used. Switching from no encoding mode to encoding mode is a change to the security light curtain and requires a new risk assessment.

4. Environmental adaptability and anti-interference

4.1 Distance requirements for reflective surfaces

Reflective surfaces such as metal walls and smooth floors may cause light reflection, leading to misjudgment of safety light curtains. When the reflective surface approaches the light curtain, the reflected light may bypass the obstructed object, causing the receiver to incorrectly detect the beam. Therefore, a minimum distance must be maintained between the safety light curtain and the reflective surface.

The calculation formula is: when the working distance is less than 3m, D = 0.131m； When the working distance is greater than or equal to 3m, D=working distance x tan (α). Among them, α is the opening angle of the beam, and the opening angle of PSEN opII4H is ± 2.5 °.

4.2 Interference suppression of multi light curtains installed in parallel

When two safety light curtains are installed in parallel and facing the same direction, measures must be taken to prevent mutual interference. There are two solutions:

Option 1: Maintain sufficient physical distance

For an uncoded light curtain, the minimum distance between two light curtains should be 2 × D (where D is the minimum distance from the reflective surface).

Option 2: Use beam encoding

Implement beam encoding (A encoding or B encoding) by connecting different pins. When using beam encoding, the minimum distance requirement between two light curtains can be reduced. The specific rules are:

When the distance between two light curtains is less than 2.5m, the minimum distance is 2 × D=262mm

When the distance is greater than or equal to 2.5m, there is no minimum distance limit

4.3 Environmental condition requirements

The safety light curtain should operate under the following environmental conditions:

Working temperature: -25 ° C to+60 ° C

Storage temperature: -40 ° C to+70 ° C

Relative humidity: 95% at 50 ° C (no condensation)

Maximum working altitude: 2000m (if exceeded, it needs to be reduced in capacity for use)

Avoid strong light, flickering light sources, smoke, fog or dust

5. Electrical connections and wiring

5.1 Pin allocation

PSEN opII4H uses a 5-pin M12 connector for electrical connection. The pin definitions of the transmitter and receiver are different:

Transmitter pin allocation:

Pin 1 (brown):+24 VDC (no coding or A-code); 0 VDC (B code)

Pin 2 (white): Reserved

Pin 3 (blue): 0 VDC

Pin 4 (black): Reserved

Pin 5 (gray):+24 VDC (no coding or B coding); 0 VDC (A-code)

Receiver pin allocation:

Pin 1 (brown):+24 VDC (no coding or A-code); 0 VDC (B code)

Pin 2 (white): OSSD 1

Pin 3 (blue): 0 VDC

Pin 4 (black): OSSD 2

Pin 5 (gray):+24 VDC (no coding or B coding); 0 VDC (A-code)

5.2 Wiring principles

To ensure the integrity of safety functions, the following principles should be followed when wiring:

Do not connect OSSD1 and OSSD2 in series or parallel

The power supply must use PELV/SELV power supply that complies with EN 60204-1 and has a buffering capacity of 20ms

The shell of the safety light curtain must be electrically isolated from the equipment (isolation can be achieved using the accompanying mounting bracket)

Cable bending radius: ≥ 5 times the wire diameter for fixed installation, ≥ 10 times the wire diameter for mobile installation