Power Electronics SD700 Series, Applications Manual, Page: 35 / 63

POWER ELECTRONICS
SD700
DESCRIPTION OF PROGRAMMING PARAMETERS
33
3.6.12. Subgroup 25.6 – S25.6: Protection
Parameter
Name /
Description
Range Function
Set on
RUN
1 PAUSE/DEL=10s
DELAY AFTER PAUS
G25.6.1 / Delay
time after
protection pause
0 to 999s
It allows setting a delay time value before the drive starts after stopping
by protection pause.
This delay time starts elapsing once the cause that produced the pause
disappears. For example: A pause was generated due to an over-
pressure. Once the over-pressure condition disappears, delay time set
here will start elapsing and when this time is elapsed, the SD700 will
start. This delay time will be applied to all of the pauses:
High pressure (analogue feedback), if it is set to PAUSE.
Cavitation, if it is set to PAUSE.
No Flow switch, if it is set to PAUSE.
Note: In case of „Cavitation‟, when the equipment goes into Pause, it is
stopped and, therefore, it is not possible to continue monitoring values, so
that, as soon as the equipment stops, delay time starts elapsing and
when this time is elapsed the equipment will start.
YES
2 CAVITATION=N
G25.6.2 / To
enable cavitation
protection
N
Y
It allows the possibility of protecting the pump from cavitation status.
OPT. FUNCTION
N=NO Cavitation protection disabled.
Y=YES Cavitation protection enabled.
To protect the pump by entering of cavitation status is necessary to follow
the next steps:
Set this parameter to „YES‟.
Set a cavitation current value (in G25.6.4) below which the first detection
condition will be met.
Set a cavitation speed value (in G25.6.5) above which the second
detection condition will be met.
Set a delay time to activate cavitation protection, once elapsed, last
cavitation condition will be activated.
Set a pause time to deactivate cavitation protection. In that moment, drive
will try to start again.
If three previous conditions are given, the drive will stop the pump to
protect it from cavitation status (no water).
YES
3 CAV MODE=FAULT
G25.6.3 /
Response from
cavitation
PAUSE
FAULT
It allows selecting the drive response from a cavitation situation.
OPT. FUNCTION
PAUSE
It will generate that the drive stops firstly, and
next, the fixed pumps. „CAVITATION PAUSE‟ will
be displayed. Once elapsed the delay time after
pause, the drive will start.
FAULT
It will generate a fault, and next, the fixed pumps
will stop. In this case, the visualization will be „F68
CAVIT/UNDERL‟.
YES
4 CAV CURR=___A
CAVITATION CURRE
G25.6.4 /
Cavitation current
(0.2 to
1.50)·In
Setting of the cavitation current below which the first detection condition
to activate the protection is met. This parameter operates together with
parameters G25.6.5 and G25.6.6. See note below.
YES
This value depends on the drive size.
Note: To adjust cavitation parameters, Power Electronics recommends, whenever it is possible, follow the next steps:

If the load is variable, adjust the application for the most frequent load value, for example, select a middle
consumption for an irrigation water pump.

Start the drive at manual speed.

Set the drive speed to the minimum functional speed (minimum flow in case of pumps) or to the minimum
operation level of your application.

Make a note of the output current and the motor speed.

Set the cavitation speed to the speed that you have made a note before.

Set the cavitation current to 6% less than the current that you have made a note before.

Set the desired activation time, for example, 10s.

Check the system, if it is necessary, set the parameters for an optimum response again.