Honeywell SYA14 Series, Manual

Page: 566 / 737

32 107004-15 EN FR26 ROW 0899 Printed in France
TIMING CONDITIONS
•
The 8 ms minimum time difference between the two SMs inputs guarantees the
detection of a permanent short circuits of any of the SMs inputs. Physically, the 2
sensors must be separated so than someone cannot actuate both of them.
•
If a new transition of a sensor SM occurs during a muting sequence, the muting
sequence is immediately stopped to avoid the permanent muting of the safety
function. The relative position of sensors SMs and the protective equipment ESPE
defines a minimum distance between 2 successive moving objects.
•
In the conveyor mode, the object must interrupt the safety light curtain
detection beams, before releasing both sensors SMs and 6s max. after the
actuation of the second sensor SM.
Two-direction muting using 4 sensors
The following example is a variation of the previous application, where 4 limit
switches are used to start a muting sequence whatever the direction of the
movement of the objects. These sensors could also be ultrasonic sensors,
photoelectric controls or inductive proximity sensors (correct operation of these
sensors is monitored by the muting module). The muting of the protective equipment
is allowed when the detected objects enter and leave the dangerous area. This
installation is recommended on applications where the entry and exit points of the
material into the dangerous zone are the same.
IMPROPER INSTALLATION
•
The activation of the SM sensors starts the muting sequence, but the electrical
connections must be made in such a way that the release of the protective
equipment beams stops the muting sequence (refer to the figure 4.18 of the chapter
4.9.1 Use in the conveyor mode).
•
The distance between SM1a & SM2a switches and the distance between SM1b
& SM2b switches must not allow a person to actuate both sensors within the preset
time frame tmax to avoid the unexpected start of a muting sequence.
•
To start a muting sequence, SM1a & SM2a must be interrupted within the preset
time frame 8 ms < t < tmax. This condition must also be respected for SM1b &
SM2b. The setting of the timing tmax also sets the muting maximum duration
∆
max : select
the tmax timing corresponding to the shortest muting duration
∆
max enabling the object
transfer (refer to chapter 2.4.2 SM inputs).
Failure to comply with these instructions could result in death or serious
injury.