Operation
Diaphragm Vacuum Pump N 828 / N 838
34
Translation of original Operating and Installation Instructions, english, KNF 121249-121517 09/19
7.2. Control functions (for pumps with brushless
DC motor)
7.2.1. Speed control
DC-B (constant speed)
The motor drives the pump at a constant, unchangeable speed
across the entire permissible pressure range.
.29DC-B (regulated speed)
The motor drives the pump at a changeable speed between n
min
and n
max
. Speed is specified via the control voltage.
7.2.1.1. Speed input (.29 versions)
The speed range of n
min
… n
max
is shown scaled to the control volt-
age U
Ctrl
:
▪
U
Ctrl min
0.1 V
▪
U
Ctrl max
5.0 V
If the control voltage is less than U
Ctrl min
, the motor is OFF.
Fig. 22: Control-voltage/speed curve (standard)
Speed is specified through the 8-pin controller connection (white
wire, see Tab. 13).
Optional analog settings for control voltage input
The following additional settings can be made at the factory upon
request:
▪
Modify control voltage values U
Ctrl min
and U
Ctrl max
▪
If the control voltage is less than U
Ctrl min
, the motor will be
ON.
Speed range
Speed specification