Version 10.12.2019
page 14
WERAC Elektronik GmbH
6.11
Definition of the different possible operating modes for the control unit WGN 110
6.11.1 WGN 110
Additional to its normal function as ESPE (mode 0) the control unit WGN 110 has three more
operating modes. The additional modes (mode 1, mode 2 and mode 3) allow to bypass the
light grid (LG) respectively reduced resolution or fixed blanking of lines of the light grid.
To use the modes 1 to 3 the control unit WGN 110 is equipped with two type 4 inputs,
according to PL e, contact pair 1
(B1/B2 and B3/B4) and for contact pair 2 (B5/B6 and B7/B8)
in each case to connect two floating normally open (NO) contacts e.g. for a two-channel safety
equipment.
The following operation modes are distinguished:
- Mode 0 Monitoring with the ESPE (like WGN 100)
- Mode 1 Mode 0 + Bypassing the LG with contact pair 1/ Bypassing the LG with contact
pair 2
- Mode 2 Mode 0 + Reduced resolution with contact pair 1/ Bypassing the LG with contact
pair 2
- Mode 3 Fixed Blanking + Bypassing the LG with contact pair 1/ Bypassing the LG with
contact pair 2
In mode 0 the control unit WGN 110 behaves exactly like the WGN 100. The additional inputs/
contacts are not evaluated.
Caution!
When using mode 2 it should be noted that the function ”bypassing the light grid” has a higher
priority than reduced resolution. E.g. if both contact pairs are activated the function bypassing
is selected. (Details can be found in chapter 6.11.6 and 6.11.7)
6.11.2 Bypassing the light grid (LG)
If an operating mode with bypassing the light grid was selected in the alignment mode, the
safety function of the light grid can be bypassed with contact pair 1 and 2 in mode 1 and 3
(bypassing the lightgrid or fixed blanking). In mode 2 the light grid can be bypassed only with
contact pair 2. To activate the bypassing both NO contacts of a contact pair must close within
one second. As long as the light grid is bypassed by the two NO contacts no monitoring of the
guarded area takes place, i.e. an interruption of the light grid will not be detected!
During mode 1, 2 and 3 the connected inputs/ contacts were monitored dynamically.
The use of the function “bypassing the light grid” is only allowed for applications were the risk
assessment showed that bypassing is permissible.
6.11.3 Reduced resolution (blanking of light beams)
If operating mode 2 was selected in the alignment mode, contact pair 1 can activate the
blanking of the teached-in lines. To activate the blanking mode both NO contacts of contact
pair 1 must close within one second.
As long as the blanking function is activated by the two NO contacts, only the remaining part
of the guarded area is monitored, i.e. an interruption of the light grid in the teached-in blanking
area will not be detected!
During mode 2 the connected inputs/ contacts were monitored dynamically by the control unit.
The blanked light beams are determined in an extra teach-in function within the alignment
mode. Then they are saved in the internal memory of the control unit.
The use of the function switched blanking is only allowed for applications were the risk
assessment showed that blanking is permissible.
