Carrier 19EF Series, Руководство по запуску и эксплуатации

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If, after configuring a value for these points, surge pre-
vention is operating too soon or too late for conditions, these
parameters should be changed by the operator.
Example of configuration: Machine operating parameters
Refrigerant used: HFC-134a
Estimated Minimum Load Conditions:
44 F (6.7 C) LCW
45.5 F (7.5 C) EWC
43 F (6.1 C) Suction Temperature
70 F (21.1 C) Condensing Temperature
Estimated Maximum Load Conditions:
44 F (6.7 C) LCW
54 F (12.2 C) ECW
42 F (5.6 C) Suction Temperature
98 F (36.7 C) Condensing Temperature
Calculate Maximum Load — To calculate maximum load
points, use design load condition data. If the machine full
load cooler temperature difference is more than 10° F
(5.6 C), estimate the refrigerant suction and condensing tem-
peratures at this difference. Use the proper saturated pres-
sure and temperature for the particular refrigerant used.
Suction Temperature:
42 F (5.6 C) = 37.1 psig (256 kPa) saturated
refrigerant pressure (HFC-134a)
Condensing Temperature:
98 F (36.7 C) = 120.1 psig (828 kPa) saturated
refrigerant pressure (HFC-134a)
Maximum Load
D
T2:
54 – 44 = 10° F (12.2 – 6.7 = 5.5° C)
Maximum Load
D
P2:
120.1 – 37.1 = 83 psi (828 – 256 = 572 kPa)
To avoid unnecessary surge prevention, add about 5 psi
(34 kPa) to
D
P2 from these conditions:
D
T2 = 10° F (5.5° C)
D
P2 = 88 psi (606 kPa)
Calculate Minimum Load — To calculate minimum load con-
ditions, estimate the temperature difference that the cooler
will have at 10% load, then estimate what the suction and
condensing temperatures will be at this point. Use the proper
saturated pressure and temperature for the particular refrig-
erant used.
Suction Temperature:
43 F (6.1 C) = 38.1 psig (263 kPa) saturated
refrigerant pressure (HFC-134a)
Condensing Temperature:
70 F (21.1 C) = 71.1 psig (490 kPa) saturated
refrigerant pressure (HFC-134a)
Minimum Load
D
T1:
45.5 − 44 = 1.5° F (7.5 – 6.7 = 0.8° C)
Minimum Load
D
P1:
71.1 − 38.1 = 33 psig (490 – 263 = 227 kPa)
Again, to avoid unnecessary surge prevention, add 5 psi (34
kPa) at
D
P1 from these conditions:
D
T1 = 1.5° F (0.8° C)
D
P1 = 38 psi (261 kPa)
If surge prevention occurs too soon or too late:
LOAD
SURGE PREVENTION SURGE PREVENTION
OCCURS TOO SOON OCCURS TOO LATE
At low
loads
(
,
50%)
Increase P1 by 5 psi
(34 kPa)
Decrease P1 by 5 psi
(34 kPa)
At high
loads
(
.
50%)
Increase P2 by 5 psi
(34 kPa)
Decrease P2 by 5 psi
(34 kPa)
Modify Amp Correction Factors — To modify the amp cor-
rection factor, use the values listed in Table 6. Enter the ap-
propriate amp correction factor in the Service1 table of
Equipment Service.
MODIFY EQUIPMENT CONFIGURATION IF NECES-
SARY — The Equipment Configuration table has tables to
select and view or modify. Carrier’s certified drawings will
have the configuration values required for the jobsite. Modify
these tables only if requested.
Config Table Modifications — Change the values in this table
per job data. See certified drawings for values. Modifica-
tions include:
• chilled water reset
• entering chilled water control (Enable/Disable)
• 4-20 mA demand limit
• auto restart option (Enable/Disable)
• remote contact option (Enable/Disable)
Owner-Modified CCN Tables— The following tables are de-
scribed for reference only.
Occdef Table Modifications — The Occdef tables contain
the Local and CCN time schedules, which can be modified
here, or in the Schedule screen as described previously.
Holidef Table Modifications — The Holidef tables configure
the days of the year that holidays are in effect. See the holi-
day paragraphs in the Controls section for more details.
Brodefs Table Modifications — The Brodefs screen defines
the outside-air temperature sensor and humidity sensor if one
is to be installed. It will define the start and end of daylight
savings time. Enter the dates for the start and end of daylight
savings if required for the location. Brodefs also will acti-
vate the Broadcast function which enables the holiday pe-
riods that are defined on the LID.
Other Tables — The Alarmdef, Cons-def, and Runt-def con-
tain tables for use with a CCN system. See the applicable
CCN manual for more information on these tables.
These tables can only be defined through a CCN Building
Supervisor.
CHECK VOLTAGE SUPPLY — Access the Status 01
table and read the actual line voltage. This reading should be
equal to the incoming power to the starter. Use a voltmeter
to check incoming power at the starter power leads. If the
readings are not equal, an adjustment can be made to the
24-v input to the SMM at the potentiometer located in the
low-voltage section of the starter to equalize the two
readings.
PERFORM AN AUTOMATED CONTROL TEST — Check
the safety controls status by performing an automated con-
trols test. Access the Control Test table and select the Au-
tomated Tests function (Table 7).
The automated control test will check all outputs and in-
puts for function. It will also set the refrigerant type. The
compressor must be in the OFF mode in order to operate the
control test and the 24-v input to the SMM must be in range
(per line voltage percent on Status01 table). The OFF mode
is caused by pressing the STOP pushbutton on the LID. Each
test will ask the operator to confirm that the operation is oc-
curring, and whether or not to continue. If an error occurs,
the operator has the choice to try to address the problem as
the test is being done, or to note the problem and proceed to
the next test.
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