Honeywell SYA14 Series Manual page 596

4.7.2 FSDs monitoring loop (terminals 26-27)
The FSDs monitoring loop is provided by the RESTART input. (see chapter 4.8.2).
The Normally Closed contacts of the two FSDs relays K1 and K2 or FF-SRE extension
module must be connected in series between terminals 26-27 to check correct operation of
the FSDs each time the OSDs outputs switch. If a failure of the FSDs relays K1 and K2 or
FF-SRE extension module is detected, the OSDs outputs remain open until the failure is
removed.
IMPROPER EXTERNAL SAFETY RELAYS PERFORMANCE
•
Use two independent stop circuit safety relays K1 and K2 with mechanically linked
contacts (such as GE CR120 BP Machine Tool Relay or Telemecanique CA3-KN31BD3 or
CA3-DN31BD relay) or FF-SRE extension module to reliably detect a welded contact.
•
Always use the FSD monitoring loop to check correct operation of relays K1 and K2.
Failure to comply with these instructions could result in death or serious injury
Figure 4.12 : Connection of the FSDs monitoring loop
+24Vdc
2.5A
P/B3
K1 K2
32 27 26
+24V
OUTPUT
RESTART
FF-SRM
2
Machine
control
K2
circuitry
K1
0 V
Features RESTART input
Type voltage presence and without reference potential
Dynamic signal pic of 50 mA min.
NC contacts 50 Ohms max. resistance
Protections galvanic insulation : 500 Vdc
62
FSD
K1 *
25
OSD1
OSD2
8
FSD
K2 *
107004-15 EN FR26 ROW 0899 Printed in France