Hmax Update; Differential Pressure From Two Sensors; Start Delay After Power-Up; Auto/Manual Restart After Alarm - Grundfos CUE Series Product Manual

Functions

Hmax update

Setting via PC Tool.
This function is used in connection with the control
mode Proportional differential pressure. The purpose is
to find the "true" value of the maximum head at no flow
and nominal pump speed. See fig. 32.
H
max.
Fig. 32 Proportional differential pressure, H
The function consists of two steps:
1. Ramping up the speed to nominal speed.
2. Measuring Hmax for 20 seconds at nominal speed.
Valves must be closed so that the pump is operating
without flow.
Differential pressure from two
sensors
Setting via PC Tool.
The purpose of this function is to make differential pres-
sure control possible by using measurements from two
separate pressure sensors.
It can be used in these control modes:
• Proportional differential pressure. See page 15
• Constant differential pressure. See page 15.
The function requires an MCB 114 sensor input mod-
ule.
Sensor 2
Fig. 33 Differential pressure from two sensors
Sensor 1 is connected to the sensor input 1.
26
CUE
Δp
update
max
CUE
Sensor 1
Δp
Sensor 2 is connected to the sensor input 2 of an MCB
114 sensor input module.

Start delay after power-up

Setting via PC Tool.
The start delay after power-up is a delay between
power being applied and the pump starting.
Power on:
Start CUE:
Start delay
Fig. 34 Start delay after power-up
The purpose is to allow remote control equipment to
start up before the pump.
The start delay is deactivated if a remote command is
received via GENIbus.

Auto/manual restart after alarm

Setting via PC Tool.
In case of an alarm, the CUE will stop the pump or
change the operating mode, depending on the alarm
and pump type. See Warning and alarm list on page 38.
Pump operation will be resumed when the cause of the
alarm has been remedied and the alarm has been reset
automatically or manually.
The CUE can be configured to activate and deactivate
automatic restart for all alarms or for groups of alarms.
Grundfos CUE
Time