8
Signet 9900 Conductivity Transmitter
PWR +
PWR –
Loop +
Loop –
OC –
OC+
Power
Supply
V+
Gnd
Alarm
with NORMAL set to OPEN.
If PLC needs 0 logic input when relay
is not energized, set NORMAL to
CLOSED in the RELAY menu when
using the Open Collector (R1) with
NPN style wiring.
PWR +
PWR –
Loop +
Loop –
OC –
OC+
Pull-Up Resistor
..ȍ:
Power
Supply
9WR9
Gnd
PLC
Gnd
Input
NPN Style Wiring
Open Collector Wiring
OC+
Pull-Down Resistor
..ȍ:
3:5
3:5±
Loop +
/RRS±
2&±
PLC
Gnd
Input
Power
Supply
+5V to +24V
Gnd
PNP Style Wiring
• The 9900 Open Collector (R1) output provides high-speed switching capability.
Signal frequencies can reach 400 pulses per minute.
• The 9900 Open Collector (R1) output connection is dependent upon the type of circuit being
controlled by the output.
• Most indicating instruments or control system inputs require a signal voltage of 0 to 5 V (TTL or
CMOS logic levels) or 0 to 24 V. Therefore, the 9900 Open Collector output circuits must be equipped
with a pull-up or pull-down resistor (not supplied), and a quality regulated 5 to 24 V (depending on the
application) power supply (not supplied) is recommended to function properly.
Relay and Open Collector Wiring
