Setpoint; Setpoint Examples; Bacnet Communication Watchdog; Fault Monitoring And Resetting - Grundfos CIU 300 Functional Profile And User Manual

7.2 Setpoint

This object accepts values ranging from 0 to 100 (0 % to 100 %).
This is illustrated in fig. 9.
The setpoint is a percentage of the maximum setpoint
Note
or sensor maximum (max. = 100 %).
The setpoint value can represent speed, pressure, flow, etc.,
depending on the selected control mode.
A setpoint of 0 does not imply a stop.
Sensor
maximum
Minimum
setpoint
0 % Setpoint [%]
Fig. 9 Setpoint

7.2.1 Setpoint examples

Closed loop
If the control mode is set to Constant pressure (closed loop) and
the pressure sensor is in the range of 0 to 10 bar, a setpoint of
80 % will result in an effective setpoint of 8 bar.
If the sensor range was 0 to 16 bar, a 50 % setpoint would be 8 bar,
a 25 % setpoint would be 4 bar, and so on.
10 bar
8 bar
0 %
Fig. 10 Constant pressure
Open loop
If the control mode is set to Constant speed (open loop), the
setpoint is interpreted as setpoint for the booster performance.
Maximum
booster
performance
50 % system
performance
0 %
Fig. 11 Constant speed
18
100 %
80 % 100 %
100 %
50 %

7.3 BACnet communication watchdog

A BACnet communication watchdog is implemented in the
CIM/CIU 300. If no BACnet communication is detected for the time
period defined by the BACnet watchdog object (AV, 1), and the
control source of the booster is set to Bus control (BO, 0), the
CIM 300 will make the booster run with the settings defined in
local mode.
This functionality can be used to define the booster behaviour in
case of a BACnet communication breakdown. Before enabling the
watchdog, the local booster settings should be made with either
a Grundfos PC Tool or the Grundfos R100 remote control (for
Multi-E only). This ensures that the booster behaves as expected if
the BACnet communication breaks down.
When BACnet communication is re-established after a watchdog
timeout, the booster will run with the remote settings again.
When the Present_Value of the AV, 1 object is set to 0, the
watchdog is disabled (default). To enable the watchdog, set the
Present_Value to [5-3600] seconds.

7.4 Fault monitoring and resetting

This example shows how to monitor faults or warnings in the
booster and how to manually reset a fault.
The Fault code object (AV, 0) and the Warning code object (AV, 1)
can both hold a Grundfos-specific fault code. See section
11. Grundfos alarm and warning codes
Warnings are notifications only, and a warning will normally not
stop the booster system.
If a fault is to be manually reset, use the Reset fault object (BO, 4).
When the Present_Value of this object is set to 1, a Reset fault
command is sent to the device.

7.5 Fault simulation example

Fault simulation can be helpful for testing alarm behaviour for
a Hydro MPC booster system. The system will behave exactly as if
a real alarm was present.
This example shows how to simulate a "Pressure high" alarm on
a Hydro MPC that will result in a stop of all pumps, and require
manual resetting.
• Set "Simulation event code" (AV, 4) to 210 (Pressure high).
• Set "Simulation device type" (AV, 5) to 8 (System).
• Set "Simulation device number" (AV, 6) to 1 (System).
• Set "Simulation event action type" (AV, 7) to 0 (Stop).
• Set "Simulation event reset type" (AV, 8) to 0 (Manual
resetting).
• Set "Fault simulation" (BO, 5) to 1 (Enabled).
• The CU 351 will now enter into the system mode "Event action",
and in this case stop all pumps, and the red LED on the CU 351
will be on. On the CU 351 display, the "Pressure high" alarm is
indicated.
• Read "Fault simulation status" (BI, 28), and see that it is set to 1
(Fault simulation enabled).
• Remove the simulated alarm settings by setting "Fault
simulation" (BO, 5) to 0 (Disabled).
• Reset the alarm via the CU 351 display or via the BACnet object
"Reset fault" (BO, 4), and the CU 351 will go back to normal
operation.
for code interpretation.