Elma LC130H, Service Manual, Page: 49 / 109

Faulty PXE transducer disks
© Elma GmbH & Co KG SM/Transsonic_LC/1104/D
47
Another possibilty to check the transducer system is to test-
operate the generator at the transducer system,
see section
15.1.
In case of a short circuit the measured graph (oscilloscope) can
look like the current graph in
Illustration 15.2.4
in
section 15
.
Torn PXE transducer disks can remain undetected as output,
transducer behaviour and current diagram are normal.
Another hint concerning a fault of the transducer system can be
an overheated (dark) secondary coil of the output transformer.
This can also be caused by improper loading of the tank
(cleaning items directly on the tank floor) or a running dry of the
tank.
To carry out this repair work a torque wrench is indispensable!
PXE transducer disk: 200 000 5046
Aluminum washer: 200 000 5050
Caution!
Risk of electrocution due to high amount of electricity
on PXE disks!
The PXE transducer disk is charged with a high amount of
electricity when opened or tightened. This can be branched off
by short circuiting between two terminal lugs, e.g. with a screw
driver. For the same reason, also short circuit the plug contacts
of the electric cables of the transducer system.
The electric charge is also built up by a temperature change,
i.g. cooling of a PXE disk.
Do not touch charged PXE disks!
Replace PXE transducer disks as follows:
Tool
Elma Order No.
Elektric load
How to open the
transducer system
1. Place the unit upside down on a solid surface and secure it
against displacement (e.g. with screw clamps and wood
ledges).
2. Open the unit as described in
section 7
.
3. Open the transducer system screw(s) with the torque
wrench.
Caution!
Do not tear the transducer system by jamming the
torque wrench.
The torque wrench must be held vertically to the transducer
system during the complete process of unscrewing. The
power given to the handle of the tool must be exactly
countered by the hand that centers the tool (
see Illustration
10.1.
).