Main Menu - Application Functions - Group; Sleep Mode - Danfoss VLT HVAC Basic Drive Programming Manual

Parameters
3.15 Main Menu - Application Functions -
Group 22

3.15.1 22-4* Sleep Mode

The purpose of sleep mode is to allow FC101 to stop itself in
situations where the system is satisfied. This will save energy,
and keeps system from being over-satisfied (too high
pressure, water cooled too much in cooling towers, building
pressurisation problems). This is also important for a reason
that some applications cannot allow the FC101 to adjust
motor down to low speed. This might damage pumps, cause
insufficient lubrication in gearboxes, and make fans unstable.
Sleep controller has two important functions - ability to go to
sleep at right time, and ability to come out of a sleep mode
at right time. The goal is to keep FC101 in sleep mode as
long as possible to avoid cycling the motor on and off
frequently, and at the same time keep the controlled system
variable in acceptable range.
The sequence when running sleep mode in Open Loop:
1. The motor speed is less than 22-47 Sleep Speed [Hz]
and the motor has been running longer than
22-40 Minimum Run Time.
2. FC101 ramps the motor speed down to1-82 Min
Speed for Function at Stop [Hz].
3. FC101 activates 1-80 Function at Stop. The
frequency converter is now in sleep mode.
4. FC101 compares the speed setpoint with
22-43 Wake-Up Speed [Hz] to detect wake up
situation.
5. The speed setpoint is greater than22-43 Wake-Up
Speed [Hz] and the sleep condition has last for more
than 22-41 Minimum Sleep Time. The frequency
converter is now out of sleep mode.
6. Go back to speed open loop control (ramp motor
speed up to the speed setpoint).
The sequence when running sleep mode in Closed Loop:
1. The motor speed is less than22-47 Sleep Speed [Hz]
and the motor has been running longer than
22-40 Minimum Run Time.
2. FC101 activates the boost function (add the
22-45 Setpoint Boost to the setpoint). The frequency
converter is now in sleep boost mode.
3. The new setpoint has been achieved or sleep boost
has been running for longer than 22-46 Maximum
Boost Time)
4. FC101 ramps the motor speed down to 1-82 Min
Speed for Function at Stop [Hz].
5. FC101 activates 1-80 Function at Stop. The
frequency converter is now in sleep mode.
VLT HVAC Basic Drive Programming Guide
NOTE
Sleep Mode will not be active when Local Reference is active
(set speed manually by means of arrow buttons on the
LCP).
Does not work in Hand-mode. Auto set-up in open loop
must be carried out before setting input/output in closed
loop.
22-40 Minimum Run Time
Range:
10.0 s
22-41 Minimum Sleep Time
Range:
10.0 s
22-43 Wake-Up Speed [Hz]
Range:
10.0 Hz
22-44 Wake-Up Ref./FB Diff
Range:
10.0 %
®
MG.18.B1.02 - VLT is a registered Danfoss trademark
6. FC101 compares process setpoint (without boost)
with feedback to detect wake up situation.
7. The error (setpoint - feedback) is greater
than22-44 Wake-Up Ref./FB Diff and the sleep
condition has last for more than22-41 Minimum
Sleep Time The frequency converter is now out of
sleep mode.
8. FC101 goes back to closed Loop control.
Function:
[0.0 - 600.0 s] Set the desired minimum running time for
*
the motor after a start command (digital
input or Bus) before entering Sleep Mode.
Function:
[0.0 - 600.0 s] Set the desired Minimum Time for staying
*
in Sleep Mode. This will override any wake
up conditions.
[0.0 - 400.0 Hz]
*
Function:
[0.0 - 100.0 Only to be used if 1-00 Configuration Mode
*
%] is set for Closed Loop and the integrated PI
controller is used for controlling the
pressure.
Set the pressure drop allowed in
percentage of set point for the pressure
(Pset) before cancelling the Sleep Mode.
3 3
Function:
69