Danfoss VLT AQUA Drive FC 202 Programming Manual page 242

Parameter Description
3.25.5 29-5* Flow Confirmation
The flow confirmation feature is designed for applications
where there is a need for the motor/pump to run while
waiting for an external event. The flow confirmation
3 3
monitor expects to receive a digital input from a sensor on
a gate valve, flow switch, or a similar external device,
indicating that the device is in the open position and flow
is possible. In parameter 29-50 Validation Time, define for
how long the VLT
input signal from the external device to confirm the flow.
After the flow is confirmed, the frequency converter checks
the signal again after the flow verification time and then
runs normally. The LCP status reads Verifying flow while the
flow monitor is active.
The frequency converter trips with the alarm Flow Not
Confirmed if the expected digital input signal becomes
inactive before either the flow validation time or the flow
verification time expires.
N
MAX
1
N
MIN
0
2
1
0
3
1
4 0
1
0
1 Speed curve.
2 Start command (for example, terminal 18).
3 Digital signal from an external device that confirms that
the flow is possible.
4 Flow verification.
t Start command issued (for example, terminal 18 is set
0
active).
t Digital signal from an external device becomes active
1
before parameter 29-50 Validation Time expires.
t When parameter 29-51 Verification Time passes, the
2
frequency converter checks the signal from the external
device again and then runs normally.
Illustration 3.115 Flow Confirmation
240
VLT
®
AQUA Drive FC 202 waits for the digital
t0 <t1 t2
Danfoss A/S © 05/2018 All rights reserved.
®
AQUA Drive FC 202
29-50 Validation Time
Range:
Size
related
*
29-51 Verification Time
Range:
15 s [ 0.10 -
*
255 s]
T
29-52 Signal Lost Verification Time
T
Enter the length of the delay after which the signal is considered
to be lost. This parameter is ignored if parameter 29-53 Flow
Confirmation Mode is set to [0] Confirmation Only.
T
Range:
1 s
*
T
29-53 Flow Confirmation Mode
Select the operating mode of the flow monitor function.
Option:
[0] Confirmation
*
Only
[1] Monitor and
Stop
[2] Monitor and
Coast
Function:
NOTICE
[ 0 -
999 s]
Parameter 29-50 Validation Time is
only visible in the LCP if a digital
input is set to [86] Flow Confirmation
(see parameter group 5-1* Digital
Inputs).
The digital input from an external device
must be active during the validation time.
Function:
NOTICE
Parameter 29-51 Verification Time is only
visible in the LCP if a digital input is set
to [86] Flow Confirmation (see parameter
group 5-1* Digital Inputs).
When the time in this parameter passes, the
frequency converter checks the signal from the
external device. If the signal is active, the
frequency converter runs normally.
Function:
[0.01 - 255 s]
Function:
The flow confirmation function is only
active during the start-up of the pump.
The flow confirmation function is active
during and after the pump start-up. The
frequency converter performs a ramp
down to a stop if the input signal is lost.
The flow confirmation function is active
during and after the pump start-up. The
frequency converter performs coasting if
the input signal is lost.
MG20OB02