Instruction Manual VisGuard 2 E xtractive
Troubleshooting on additional components
32
14265E/1
9.2
Malfunctions on the sample heater KW5
The sample heater KW5 is made up of a metal pipe with an integrated resistance wire as he-
ating element. The only conceivable malfunction here is an interruption in the supply line or
a wire breakage.
The electrical resistance between the sample heater connections should be between 900 and
1,500 Ohm. This can be measured with an ohmmeter. If this is not the case, the entire
sample heater must be replaced (Section 10.1).
9.3
Malfunctions on the valve unit ST2MP3
The valve unit ST2MP3 is essentially made up of pipes and electromagnetic valves. The foll o-
wing malfunctions can occur:
Fault during valve actuation by the control unit.
Check actuation of the valves directly on the controller using a voltmeter (
documentation
for the control unit). Depending on the valve type (open or closed de -energized), the actua-
tion voltage must be present or zero if the measured measuring point is currently active. If
this is not the case, examine the controller for the cause (
documentation for the control
unit).
Interruption in the electrical supply line.
Check actuation of the valves directly on the valve connections using a voltmeter. Depending
on the valve type (open or closed de-energized), the actuation voltage must be present or
zero if the measured measuring point is currently active. If this is not the case, the electrical
supply line must be replaced.
Interruption in the coil of one or more valves.
When the sampling system is turned off and connection cable is disconnected, the electrical
resistance can be measured directly on the valve connections using a voltmeter. If the electri-
cal resistance is not within the limits defined in the following table, the corresponding valve
is defective and must be replaced.
Valve type
Resistance value
24 VDC
47 .. 57
Mechanical blocking of one or more valves.
If the malfunction cannot be rectified with the aforementioned steps, a mechanical blocking
of a valve must be assumed. The valve or valve unit must be replaced in this case
(Section 10.2).
