ZENER VARIDRIVE SOLUTIONS
ZENER ECODRIVE® 8000
IM00130
P a g e
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20/07/2018 3:59 PM
IMPLEMENTING ‘IDLE MODE’
What is Idle Mode ?
Idle mode is a feature that automatically switches the pump off when a ‘no flow’ condition is detected. The pump will then
restart based on pressure (‘% below SV’) [DEFAULT] or PID output (‘output frequency’).
There are 2 methods in which the ‘Idle Mode’ can be triggered.
1.
“% LOAD” [DEFAULT] Monitoring the ‘% Load’ to indicate when the pump load represents a no flow situation. Idle
mode is triggered when the load drops to the preset level for the preset time. Depending on the pump performance
and operating conditions a flow switch may be required. Eg. Multiple set points.
2.
FLOW SWITCH [DEFAULT] Connect an external flow switch that triggers ‘idle mode’ when no flow for the preset ‘idle
delay’. The switch is connected to digital input on the option board D3(35). The default setting requires a contact that
opens on ‘no flow’. This input is always active so a link is required when a flow switch is not fitted. A flow switch is the
best method to use when operated with a variable or multiple set point. The flow switch provides a more simple setup
process as the ‘% Load’ threshold is not used.
3.
OTHER [CUSTOM] Use an internal logic function or other external device to trigger idle mode.
NOTE: Both the ’% Load’ and the ‘flow switch’ methods can be used simultaneously, using the same ‘idle delay’.
Idle based on ‘% Load’
This is detected by a drop in ‘% Load’ for a set period of time. For this to operate it is important to find the ‘% Load’ under a ‘No
Flow’ or ‘Dead head’ condition. Pumping will resume when the pressure falls below a specified % below the Set point. A flow
switch can also be installed to trigger the idle mode.
To ensure correct operation the ‘Idle’ function must be checked and configured for all possible conditions. For installations
where multiple or variable set points the ‘% load’ method may not operate under all conditions and require a flow switch to
be installed.
time
PV feedback
Output Speed
% Load
PV feedback
H104 RESUME AT
PV threshold
H100 IDLE %LOAD
H101 IDLE DELAY
ZENER 8000 is idle
IDLE:
‘% Load’ decreases with reduced flow to a level for a period of
time ‘Idle Delay’ and then goes into ‘Idle Mode’ (sleep). Or ;
The input from the optional Flow Switch indicating ‘No Flow’ for
the ‘Idle Delay’.
WAKE:
When the pressure drops due to returned demand the
ZENER 8000 wakes automatically and operates in PID mode.
