Honeywell SYA14 Series Manual page 733

APPLICATION EXAMPLES (continued)
FIG. 11.: DUAL-CHANNEL SAFETY DOOR MONITORING
(WITH CROSS-FAULT MONITORING, AUTOMATIC START MODE )
S1 Cross fault detection
with
S2 Start mode
automatic
Actuated normally open
contact:
closed position
GENERAL DESCRIPTION OF SAFETY DOOR APPLICATIONS
Protective gates are designed to limit or block access to the moving parts of dangerous machinery. These
gates can be equipped with locking or interlocking devices, usually safety limit switches or any other safety
sensors/switches.
The FF-SRS5925 Emergency Stop module monitors the status of these safety sensor positions. When the
protective gate is open, the initiation of dangerous motion is prevented. When the door is closed again, the
next machine cycle can start, but only after initiating an external manual restart sequence.
FUNCTIONAL DESCRIPTION
After opening the door, the two external safety switch contacts Sa and Sb will open (as illustrated above) and
the two internal safety relays K1 and K2 will de-energize. The normally open safety outputs 13/14 and 23/24
will open relaying the stop condition to the machine control circuitry. After closing the door, Sa and Sb close
and the internal relays K1 and K2 will energize automatically. The two normally open safety contacts will
close and an external manual restart sequence may then be initiated (allowing the machine to operate).
IMPROPER AUTOMATIC START MODE IN PERIMETER GUARDING APPLICATIONS
• If the module is in the automatic start mode, another part of the safety control circuitry must keep the
latched function engaged.
Failure to comply with these instructions could result in death or serious injury.
• The cable resistance between S11/S12 and S21/S22 must be less than 68Ω (ohms) for correct operation
of the safety control module.
• A minimum of 21 Vdc must be present between each channel input (S12/A2 and S22/A1) to ensure the
correct detection of sensor(s) outputs status.
9
24Vdc/ac (+)
Fuse
0V (-)
closed
Sa
Sliding guard
(closed position)
Sb
open
Honeywell
FF-SRS 5925
107035-02 EN FR26 ROW 0499 Printed in Germany
Power
Fuses
23 31
24 32
Machine
Control