Emerson COPELAND ZO18AG, Инструкции по применению

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AGL_Ref_ST_ZO_E_Rev00 23
5.6 Run-in time
Scroll compressors exhibit a slight decrease in input power during the initial running period.
Published performance ratings are based on calorimeter testing which is carried out after run-in.
Therefore, users should be aware that before the performance specified by EN 12900 is achieved
the compressor needs to be run in. Recommended run-in times for
ZO(V)*AG compressors to attain
the published performance are 16 hours at the standard conditions.
5.7 Initial start-up
CAUTION
High discharge pressure operation! Compressor damage!
Do not use
compressor to test opening setpoint of high-pressure cut-out. Internal parts
are susceptible to damage before they have had several hours of normal
running in.
Liquid and high-pressure loads could be detrimental to new bearings. It is therefore important to
ensure that new compressors are not subjected to liquid abuse and high-pressure run tests. It is not
good practice to use the compressor to test the high-pressure switch function on the production line.
Switch function can be tested with nitrogen prior to installation and wiring can be checked by
disconnecting the high-pressure switch during the run test.
5.8 Rotation direction
Scroll compressors, like several other types of compressors, will only compress in one rotational
direction. All three-phase compressors will rotate in either direction depending upon phasing of the
power. Since there is a 50-50 chance of connecting power in such a way as to cause rotation in the
reverse direction,
it is important to include notices and instructions in appropriate locations
on the equipment to ensure proper rotation direction when the system is installed and
operated
.
Observing that suction pressure drops and discharge pressure rises when the compressor is
energized allows verification of proper rotation direction. There is no negative impact on durability
caused by operating three-phase Copeland scroll compressors in the reversed direction for a short
period of time (under one hour) but oil may be lost. Oil loss can be prevented during reverse rotation
if the tubing is routed at least 15 cm above the compressor. After several minutes of operation in
reverse, the compressor's protection system will trip due to high motor temperature. The operator
will notice a lack of cooling. However, if allowed to repeatedly restart and run in reverse without
correcting the situation, the compressor will be permanently damaged.
All three-phase scroll compressors are identically wired internally. Therefore, once the correct
phasing is determined for a specific system or installation, connecting properly phased power leads
to the identified compressor terminals will ensure proper rotation direction.
5.9 Start-and-stop routine
The drive controls the start-and-stop routine of the variable-speed scroll. This routine allows for soft
starting and controlled stopping, an advantage over traditional On/Off control of fixed capacity units.
NOTE: For more information about this topic please refer to the EVM/EVH User Manual.
5.10 Starting sound
During the very brief start-up, a clicking sound resulting from the initial contacting of the spirals is
audible; this sound is normal. Due to the design of the Copeland scroll compressors, the internal
compression components always start unloaded even if system pressures are not balanced. In
addition, since internal compressor pressures are always balanced at start-up, low-voltage starting
characteristics are excellent for Copeland scroll compressors.