Bosch CRR 120 - Fault Matrix

1 689 975 254 2014-01-14| Robert Bosch GmbH
Fault matrix | CRR 120 | 25 en
6. Fault matrix
No. Symptom (complaint) Possible cause of trouble/defective
component
Fault rectification
1 Device cannot be switched on by
way of inlet valve with red actu-
ator
Inlet valve (WAP 3/2) sticking, stiff Replace inlet valve (WAP 3/2)
2 Device pressure fluctuations/loss
of pressure (pressure gage Po)
Leakage at pneumatic system components
and connections
Check pneumatic system components and
connections for leaks
3 Device is not switched on after ac-
tuating inlet valve with red actu-
ator (display of display module
does not light)
Pressure switch not being supplied with
power, defective
Check power supply and output signal of
pressure switch, replace pressure switch
Power supply of voltage stabilizer not
switched on (24 DC)
Switch on and set voltage stabilizer accord-
ingly (24 V, I > 0.2 A)
Voltage stabilizer current limitation set-
ting too low
Switch on and set voltage stabilizer accord-
ingly (24 V, I > 0.2 A)
Protective diode defective Check/replace diode 1N4007
Fuse defective Check/replace fuse 5X20 0.5 A slow-blow
Pressure switch not being supplied with
power, defective
Check power supply and output signal of
pressure switch, replace pressure switch
4 Display of display module does
not light, no display
Display module not being supplied with
power
Check power supply at terminal strip X1
5 Pressure cannot be adjusted by
way of potentiometer P1 (display
of display module lights)
Potentiometer knob not gripping on poten-
tiometer stem
Tighten locking screw of potentiometer knob/
replace potentiometer knob
Potentiometer defective Replace potentiometer
P1/P2 selector switch defective Replace selector switch
6 Pressure cannot be adjusted by
way of potentiometer P2 (display
of display module lights)
Potentiometer knob not gripping on poten-
tiometer stem
Tighten locking screw of potentiometer knob/
replace potentiometer knob
Potentiometer defective Replace potentiometer
P1/P2 selector switch defective Replace selector switch
7 Pressure cannot be adjusted by
way of potentiometers P1 and P2
(display of display module lights)
Potentiometer knob not gripping on poten-
tiometer stem
Tighten locking screw of potentiometer knob/
replace potentiometer knob
Potentiometer defective Replace potentiometer
P1/P2 selector switch defective Replace selector switch
Pressure control valve (ED02) not being
supplied with power, defective
Check power supply to pressure control valve
(ED02)
Pressure control valve (ED02) defective Replace pressure control valve (ED02)
8 Pressure set by way of potentiom-
eters P1 and P2 is not displayed
(display of display module lights)
Pressure sensor (P WIKA) not being sup-
plied with power
Check pressure sensor (P WIKA) power sup-
ply
Pressure sensor (P WIKA) defective Replace pressure sensor (P WIKA)
9 No pressure at connection A Leakage at valve WST 5/2 (white actuator) Eliminate leakage
Valve WST 5/2 (white actuator) defective Replace valve WST 5/2 (white actuator)
10 No pressure at connection B
(pressure is displayed by pressure
gage Po)
Leakage at valve WST 5/2 (white
actuator)
Eliminate leakage
Blockage at valve WST 5/2 (white actua-
tor)
Replace valve WST 5/2 (white actuator)
Valve WST 5/2 (white actuator) defective Replace valve WST 5/2 (white actuator)