Bell & Gossett P2001489 Integrated Technologic with Sensorless Control - Manual (Page 19)

Figure 7: Terminal connections when using factory defaults
Adding an external interlock
This setup adds an external interlock signal to the factory default configuration. An
external interlock can be used in applications that operate at extreme temperatures
and/or pressures to turn off the controller and issue an alarm during an abnormal system
condition. The external interlock signal is connected to digital input 27 on the controller.
This input can be controlled by an external device such as a suction pressure switch, an
over pressure switch, temperature switch, a differential pressure switch, etc. When the
input is disconnected from the 24V supply, an alarm is issued and the controller stops the
motor. The controller will attempt to automatically restart if the Reset Mode [14-20] and
Automatic Restart Time [14-21] are set to allow automatic restarting. To prevent an
automatic restart set the Reset Mode [14-20] to Manual Reset.
Figure 8: Terminal connections for external interlock
Table 3: Parameter settings for using an external interlock
Parameter number Description Set to
5–12 Terminal 27 Digital Input External Interlock
14–20 Reset Mode Set to the desired number of
automatic resets. If a fault occurs
more than this setting a manual reset
is required. Set to Manual Reset if no
resets are allowed. Default setting is:
Automatic reset x 3.
14–21 Automatic Restart Time This is the time between when an
alarming/warning is issued and when
the controller attempts the next
restart. Default setting is 30 seconds.
Adding transducer feedback
This configuration adds a transducer for closed loop control or for external monitoring.
Use Set-up 1 for pressure control using a wired pressure transducer and Set-up 2 for flow
control using a wired flow transducer. Refer to the Commissioning section in this manual
for detail on changing set-ups.
Electrical Installation
Integrated Technologic ® with Sensorless Control INSTRUCTION MANUAL 17