Dunham-Bush ACXi 165-5SP-LN, Инструкция по установке, эксплуатации и обслуживанию

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4.0 ELECTRICAL
TABLE 4.5.5 SAMPLE RAMP TIMES (MINUTES) FOR TWO COMPRESSOR UNIT
Ramp
Rate
Setpoint
0%
Start Point
Setpoint
50%
Start Point
Setpoint
75%
Start Point
Setpoint
0.1
33.4 25.0 20.9
0.2
16.6 12.5 10.4
0.3
11.2 8.4 7.0
0.4
8.4 6.3 5.2
0.5
6.6 5.0 4.1
0.6
5.6 4.2 3.5
0.8
4.2 3.1 2.6
1.0
3.4 2.5 2.1
4.5.6 Current Limiting
(Microcomputer)
A maximum desired current is specified
by amp limit B setpoint for each
compressor. Above the B setpoint, the
compressor will not load. If the amps
rise above the A setpoint, the computer
will give an unload command to the
compressor until the current drops below
the A setpoint. The amp value in the A
setpoint should be 10% of RLA higher
than the B setpoint.
4.5.7 Staging Control
(Microcomputer)
On multiple-compressor machines, when
the microcomputer determines that a
compressor is fully loaded and
temperature is not being maintained,
another compressor is added. When
unloading, a compressor is taken off line
when the computer determines that the
remaining compressors can control water
temperature.
4.5.8 Manual Lead-Lag Control
(Microcomputer)
On multi-compressor machines, the lead
compressor can be chosen by storing 0.0
or 1.0 in the lead setpoint B position. 0.0
is for lead on compressor #1, and 1.0 is
for lead on compressor #2 (if applicable).
4.5.9 Manual Load-Unload Control
(Microcomputer)
Loading of the compressor can be
controlled manually. To place computer
in manual control, do the following:
1. Press RESET if the compressor is
locked out.
2. Obtain authorization per 4.4.4.
3. Select CONTROL POINTS on the
main Menu. Press ENTER.
4. Use up or down arrow to select the
compressor to be controlled
manually. Press ENTER.
5. Press up or down arrow to select
MAN ON. Press ENTER. The
compressor will start and operate on
manual control.
6. Use the following keys to control the
status of the compressor:
1 - Hold
2 - Load
3 - Unload
Manual control is maintained for 15
minutes after the last manual entry. After
this, the compressor reverts to automatic
control. To retain manual control, enter a
1, 2, or 3 command to the compressor at
least once
every 15 minutes. (See Item 5
above)
In manual control, to transfer from one
compressor to another or to display data,
press MENU, then continue as above.
CAUTION:
Do not start compressor
manually more than once every 15
minutes. Verify that chilled water flow
switch is closed.
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