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English
5.906-494.0 Rev. 01 (04/11)
19
Operation with gentle start
In appliances with gentle start, the trailing must be
active.
When the pressure switch is opened, the pump
will shut off with a 30 second delay.
DIP switch 2: ON = trailing active, OFF = trailing off
Switch the appliance off and back on to delete a
fault display.
Connect the indicator lamp.
Use a wire jumper on terminals 3 + 4.
Use a wire jumper on terminals 5 + 6.
Connect a contactor coil to terminals 7 + 8.
Connect voltage (24V~) to terminals 9 + 10.
Switch on the voltage supply.
The contactor must react the indicator lamp must
glow green.
The appliance is equipped with gentle start electron-
ics.
Soft start increases the motor speed gradually to
1,400 1/min and protects the circuit from overloads
when switched on
The electronics can only be replaced as one com-
plete unit. Prior to the replacement, check the cable
connections, connected components and fuses.
A Phase indicator
B Phase indicator
C Voltage supply 24V
D Connection release
E Display "On" lights up for voltage supply of 24V,
display "Run" lights up after the motor has been
started.
Possible reasons for malfunctions of the gentle
start electronics:
Overvoltage of the voltage supply (more than 27V)
Multiple motor starts per minute (30 seconds of
trailing control of the motor protection electronics
is not active).
Corrosion and/or moisture in the components.
Check whether both phases are present.
Check if the voltage supply (24V~) is present.
Jump the release on X1 5/6 (D top of image).
LED "RUN" on the circuit board lights up after 1 -
2 seconds.
1 Fastener
2 Disc
Pull out the safety bow of the traction relief.
Loosen the disc.
Take out the traction relief from the holder.
Disconnect the mains cable.
Assemble it back in the reverse sequence.
The disc must be under the safety bow.
The illustration might differ from the gun on your
model, however, the procedure is still the same.
1 Connection of high pressure hose
2 Hand lever
3 Gun
4 Power press regulator
5 Hand guide
6 Spray pipe (stainless steel)
7 Nozzle
5.5.5 Simple function test of the motor protection
electronics without appliance
5.5.6 Gentle start electronics
5.5.7 Simple function test of the gentle start elec-
tronics inside the appliance
5.5.8 Replacing the mains cable
5.6
Gun and spray pipe HD 20/15-4 and 20/
15-4