Instruction manual

Cascade Controller Option

system. Ensure that the staging frequency setting

allows the check valve to remain open.

Quick Menu 028 Par. 741 Destaging frequency

(STD DESTAGE FRQ)

Value:

0 - 100 % F

max

✭ 10%

Function:

The lead pump (pump 1 in the figure) typically

runs at minimum speed when destaging occurs.

Turning off a fixed speed pump (pump X in the

figure) creates a momentary pressure drop until the

lead pump decelerates. To avoid this, the drive

will accelerate to a Destaging frequency before

turning off the fixed speed pump.

Description of choice:

Adjust the Destaging frequency to the best

compromise to prevent momentary pressure drop

and over-pressurization during transition. A very low

value for the destaging frequency might cause the

check valve at the discharge of the lead pump to

close during the transition, which could add pressure

in the system. Ensure that the Destaging frequency

setting allows the check valve to remain open.

NOTE

Ensure that the Destaging frequency is

set within the Minimum and Maximum

frequency in par. 201 and 202.

MG.60.I5.22 - VLT is a registered Danfoss trademark