C-Series Off-Highway
Installation Manual
I 15 I
6.2.2 Painting and electrostatic charging
When using electrostatic charge for painting processes high voltages
are applied to the component/cylinder surface. These applied very high
voltages can damage or pre-damage the electronics of MTS position
measuring systems integrated into cylinders. This can be prevented
using the following metal protective caps.
The metal protective cap safeguards the contact pins and thus the
electronics of the sensor against electrostatic effects (high voltage).
It is important to note that:
• The material of the protective cap must be permanently electrically
conductive.
• The cap must not be of aluminum (aluminum is subject to oxidation
and can cause electric isolation).
• The metal protective cap must have an M12×1 thread.
• The cap must be screwed up to the connector flange plate.
• Make sure that no paint particles contaminate the thread or the
contact pins.
• The thread of the protective cap must be clean and free from paint
particles and other substances at all times.
• The metal protective cap must be tightened only so that it is hand-
tight (max. 5 Nm).
• Paint particles on the cap outside are of no concern.
• Drawing examples for the protective cap are given in the
attachment.
6.2.3 Cylinders with integrated sensors and connecting cables
or third-party connectors
G
Fig. 14: Electrostatic painting of cylinders with integrated sensors
6.3 Mounting / dismounting cylinders on mobile hydraulics
machines
As during transport, connectors, cables and cable ends should be
protected sufficiently during mounting and dismounting. Cables
conductors should not be bent or subjected to load or tensile stress.
When connecting cables are installed, make sure that the insulation is
not damaged by sharp edges.
NOTICE
Insulation tests
Part of the tests performed on mobile machines can be insulation
tests. These tests are intended to determine the dielectric strength
of the cables against the housing (insulation resistance) using
high voltages. During these tests, all sensor cables must be
disconnected, otherwise stray voltage over the sensor protective
circuitry against ground can damage these components and cause
sensor failure.
Fig. 15: Welding the cylinder with integrated sensor
NOTICE
As a rule:
Don't perform welding work on the cylinder!
6.4 Electrical and electrostatic effects
6.5 Welding
After installing the cylinder in machines, welding work on adjacent
components can be necessary. If a grounding clamp is applied directly
or too closely to the cylinder, welding currents can be transmitted to
the sensor via the cylinder and cause burning of the sensor pipe or
damage of internal sensor components. Cylinders mostly consist of
two assemblies: the lower part with the cylinder pipe and the piston
with the piston rod. These components are isolated electrically from
each other by gaskets, bearings and slide rails. This means that,
normally, no current flow is possible. With cylinders, however, the
welding current may be transmitted from the piston to the cylinder
pipe. In this case, an electrical connection causes the entire welding
current to flow through the sensor pipe and the sensor head, thus
damaging the electronics. Moreover, the cylinder and/or the gaskets
are destroyed.
NOTICE
Electrostatic painting cannot be used for sensors with connecting
cables, since the cable cannot be protected safely against the high
process voltage. Safe electrostatic painting is ensured only in
conjunction with the M12 connector system and the brass caps.
