VACUUBRAND MD 1 VARIO-SP - Manual (Page 36)

page 36 of 68
Controlling the MD 1 VARIO-SP
Connecting the cable:
As set at the factory, the pump is designed for operation
with a control signal; i.e., without a control signal, the pump
does not start!
To operate the pump without a control signal, change the
settings on the circuit board (see below)!
NOTICE
External setting of the motor speed via PWM (factory set):
PWM (pulse-width modulation; Low: 0V - 0.5V; High: 5V - 24V max.)
frame frequency: 100Hz to 1.5kHz
0% to 100% PWM: Linear increase of the motor speed:
0 rpm (at 0% PWM) to 2400 rpm (at 100% PWM)
Pump will run smoothly only at motor speeds higher
than 200 rpm.
Example: Pulse-width at a frame frequency of 1 kHz
and at 700 rpm motor speed: 0.3 ms
Selecting the control signal input:
(PWM / voltage / internal setting)
To select a control signal input other than the factory set one (PWM), the
control line at the terminal board has to be reconnected.
The control line contains four differently colored wires.
wire in control line assignment
red +24V DC (supply voltage, max 7A)
blue GND (24V)
white
PWM: 5V to max. 24V or
voltage input: 0V to 10V DC (max. 24V)
(depending on the control signal input for
motor speed)
black GND Signal