technical reference
3
21
Synrad
Firestar i401
operator’s manual
User I/O connections
Sample outputs
Firestar’s optoisolated, bi-directional switched outputs can drive small loads (50 mA max), PLC inputs,
or relays that can control higher current loads. Figure 3-14 illustrates one method of controlling a remote
warning lamp using power supplied by Firestar’s
+24 VDC Auxiliary Power
output. Remember to size
current-limiting resistor, R1, so that the current draw does not exceed 50 mA.
Figure 3-15
Firestar output driving relay
(5) +24 VDC AUXILIARY
POWER
(6) LASER ACTIVE
(12) AUX. DC POWER
GROUND
(13) OUTPUT COMMON
L
R1
USER I/O PINS
(5) +24 VDC AUXILIARY
POWER
(6) LASER ACTIVE
(12) AUX.DC POWER
GROUND
(13) OUTPUT COMMON
+V
L
USER I/O PINS
Figure 3-14
Firestar output driving warning lamp
Figure 3-15 illustrates a method for controlling a higher voltage, higher current load by using a 24V con-
trol relay. Ensure that the relay coil’s pull-in current does not exceed 50 mA. A diode or surge suppressor
must be installed across the relay coil to prevent voltage spikes from damaging Firestar outputs.