Pump Control Quick Guide
7
When the “RUN” signal is switched on (either FWD or REV), the inverter will increase the output frequency
(always after the period time defined in J38 (sec)). In order to control this rising output, some parameters
are available: F23 (Hz) controls the starting frequency, J43 the starting PID frequency and the ramp from
one to the other (F07) (sec.). Once J43 frequency level is achieved, PID control is enabled. In the same
way, when the “RUN” signal is switched off, the inverter decrease its output frequency to the level defined
in F25 (Hz) (the deceleration time is set in F08 (sec)), and stops the PID control.
Sleep Function
(related parameters: J15 (Hz), J16 (sec.))
Sleep function can be useful to stop one pump when the speed is below a rate where there is no flow
(pump doesn’t impel).
Once the demand frequency level is below this rate (the frequency when the pump begins to move the
water but not enough to create a flow) is known, parameter J15 (Hz) should be set slightly higher than
this frequency.
Through this function, is possible to avoid possible mechanical problems that could (over time) damage
pump components or ‘boil’ the water with the wasted energy causing excess pressure and leaks. In
addition, stopping the pump when it’s not really needed means, obviously, Energy Saving.
So, Sleep Function will be applied if the inverter’s demand output frequency is lower than the ‘sleep’ level
stored in parameter J15 (Hz) and it stays at a lower level for a time longer than that specified in J16 (sec).
In Figure 1.2 sleep function is shown. The deceleration time to get to the “Stop Frequency” is stored in
F08 (sec.).
Important: Sleep frequency (J15 (Hz)) must be lower than the wake-up frequency (J17 (Hz)) and must be
higher than the minimum frequency (F16=J19)
Wake-up function
(related parameters J17 (Hz), J23 (%), J24 (sec))
Wake-up function is useful to start-up a pump again that previously was stopped by the sleep function.
In order to wake up a pump, 3 conditions must be accomplished:
MV ≥ J17 (Hz)
|SV – PV|≥ J23 (%) (*)
Delay Time ≥ J24
(sec)
Manipulated value (MV,
PID’s output) must be
greater than the level
stored in J17 (the current
MV value can be ridden
from
3. OPR MNTR
inverter’s menu.)
and...
The absolute value of the process error
(the subtraction between the process
value and the set point value ) must be
greater than the percentage in J23
and...
Both conditions must be
met for longer than the
time specified in J24
(*) J23 is related with E40 and E41 function codes as follows:
(|SV – PV|) / (E40 – E41) ≥ J23 (%)
, (E40
and E41 explained on page 42).
As the three conditions have to be met in order for the pump to start, multiple start-ups due to pipe losses
can be avoided. So, we avoid waking up the pump unnecessarily or too often.
In figure 1.2 is shown how the pump wakes up when accomplishes the three conditions.
Important: Sleep frequency (J15 (Hz)) must be lower than the wake-up frequency (J17 (Hz)).
In addition, sleep frequency must be higher than minimum frequency (F16=J19)
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