Digital Inputs - Grundfos CRE Notice D'installation Et De Fonctionnement

7.7 "Digital inputs"

Pump variant
CME
CRE, CRIE, CRNE, CRKE, SPKE, MTRE
Available inputs depend on the functional module fitted in the
pump:
Function (terminal)
"Digital input 1, setup" (2
and 6)
"Digital input 2, setup" (1
and 9)
* See section 5.2.1 Identification of functional
To set a digital input, make the settings below.
Function
Select one of these functions:
"Not active".
•
When set to "Not active", the input has no function.
• "External stop".
When the input is deactivated (open circuit), the pump stops.
• "Min." (minimum speed).
When the input is activated, the pump runs at the set minimum
speed.
• "Max." (maximum speed).
When the input is activated, the pump runs at the set
maximum speed.
• "External fault".
When the input is activated, a timer is started. If the input is
activated for more than 5 seconds, the pump is stopped and a
fault is indicated. This function depends on input from external
equipment.
• "Alarm resetting".
When the input is activated, a possible fault indication is reset.
• "Dry running".
When this function is selected, lack of inlet pressure or water
shortage can be detected.
When lack of inlet pressure or water shortage (dry running) is
detected, the pump is stopped. The pump cannot restart as
long as the input is activated.
This requires the use of an accessory, such as these:
– a pressure switch installed on the inlet side of the pump
– a float switch installed on the inlet side of the pump.
• "Accumulated flow".
When this function is selected, the accumulated flow can be
registered. This requires the use of a flowmeter which can give
a feedback signal as a pulse per defined volume of water.
See section 7.19 "Pulse flowmeter" ("Pulse flowmeter
• "Predefined setpoint digit 1" (applies only to digital input 2).
When digital inputs are set to predefined setpoint, the pump
operates according to a setpoint based on the combination of
the activated digital inputs.
See section 7.14 "Predefined
The priority of the selected functions in relation to each other
appears from section 8. Description of
A stop command always has the highest priority.
40

"Digital inputs"

●
●
FM 200* FM 300*
(standard) (advanced)
● ●
- ●
module.
setup").
setpoints".
settings.
Activation delay
Select the activation delay (T1).
It is the time between the digital signal and the activation of the
selected function.
Range: 0-6000 seconds.
Duration timer mode
Select the mode. See fig. 55.
"Not active"
•
• active with interrupt (mode A)
• active without interrupt (mode B)
• active with after-run (mode C).
Select the duration time (T2).
It is the time which, together with the mode, determines how long
the selected function is active.
Range: 0 to 15,000 seconds.
T input > T1 + T2
T input > T1 + T2
Digital
input
T input
Mode A
T1 T2
Mode B
T1 T2
Mode C
T1
Fig. 55 Duration timer function of digital inputs
Factory setting
See section 10. Technical data.
T input < T1 + T2
T input < T1 + T2
T input
T1
T1 T2
T2 T1 T2