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10.8 TERMINAL COVER MOUNTING AND REMOVAL
It is not allowed to run the compressor without terminal cover properly fixed on
the terminal fence.
Before connecting a compressor, make sure that terminal cover for electrical
protection is properly seated.
The non-use or improper positioning of the terminal cover may expose the
electrical technician the risk of electric shock and fire.
Before removing the terminal cover, check if the compressor is disconnected from
the mains and disconnect all electrical components of compressors.
The terminal cover is properly fixed if side teeth lock-on holes on terminal fence.
Cover removing has to be provided with appropriate tool (e.g. screwdriver) pushing side teeth.
CAUTION
Figure 10.8 Terminal cover
10.9 THREE-PHASE ROTATION DIRECTION
Scroll compressors are directional dependent: i.e., they will compress in one rotational direction only.
On single phase compressors, this is not an issue since they will only start and run in the proper
direction (except as described in the Brief Power Interruptions, Chapter
10.10). Three-phase scrolls,
however, will rotate in either direction depending on the power of the phasing. So there is a 50/50
chance of connected power being “backwards.”
Verification of proper rotation can be made by observing that the suction pressure drops and the
discharge pressure rises when the compressor is energized. Additionally, if operated in reverse the
compressor is noisier and its current draw is substantially reduced compared to tabulated values.
Although operation of scroll in reverse direction for brief periods of time is not harmful, continued
operation could result in failure. All three-phase compressors are wired identically internally. Once the
correct phasing is determined for a specific system or installation, connecting properly phased power
leads to the same fusite terminals will maintain the proper rotation.
