magnetic bearing adjuster nut. Supporting the preload tool body in position while
performing the preload check is recommended.
Apply pressure by pushing the test plunger until a change in preload can be detected.
Releasing the test plunger will return the preload to its original position. Pressing and
releasing the test plunger slowly while performing this check is recommended.
Detection of the bearing preload can be recognised by a distinct sound. This may be
accompanied by a sensory feel through the tool and pump body. If a change in preload
cannot be detected, it may be possible to carry on with the service but with caution.
Only for nEXT1230H
If no sound can be detected at the nEXT1230H, a multi meter can be used to detect the
change of the preload.
Put one banana plug connected to the multi meter in the hole of the test plunger and
connect the other wire of the multi meter to the pump housing e.g. by connecting it
with the earth screw of the housing. Measure the electrical resistance.
When the force applied at the test plunger is lower than the preload there is no
electrical connection between the test plunger and the housing.
When the force applied at the test plunger is bigger than the preload there is an
electrical connection between the test plunger and the housing.
The set preload is measured at the moment when it changes from no electrical
connection to electrical connection.
06/2021 - ©Edwards Limited
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300872820_002_C2 - Preload check
Summary of Contents for nEXT 1230H
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