Carrier AQUAFORCE 30XA080-500 Product Data page 51

2. Unit controls shall include the following
functions:
a. Automatic circuit lead/lag.
b. Capacity control based on leaving chilled
fluid temperature and compensated by rate
of change of return-fluid temperature with
temperature set point accuracy to 0.1° F
(0.05° C).
c. Limiting the chilled fluid temperature pull-
down rate at start-up to an adjustable range
of 0.2° F to 2° F (0.1 to 1.1° C) per minute
to prevent excessive demand spikes at
start-up.
d. Seven-day time schedule.
e. Leaving chilled fluid temperature reset from
return fluid and outside air temperature.
f. Chilled water pump start/stop control.
g. Chiller control for parallel chiller applications
without addition of hardware modules and
control panels (requires thermistors).
h. Timed maintenance scheduling to signal
maintenance activities for strainer mainte-
nance and user-defined
activities.
i. Low ambient protection to energize cooler
heaters.
j. Single step demand limit control activated by
remote contact closure.
3. Diagnostics:
a. The control panel shall include, as standard,
a display:
1) Portable hand-held display module with
a minimum of 4 lines and 20 characters
per line, in clear English, Spanish, Por-
tuguese or French language.
2) Display menus shall provide clear lan-
guage descriptions of all menu items,
operating modes, configuration points
and alarm diagnostics. Reference to fac-
tory codes shall not be accepted.
b. Information included for display shall be:
1) Compressor lockout.
2) Loss of charge.
3) Low fluid flow.
4) Cooler freeze protection.
5) Thermistor and transducer malfunction.
6) Entering and leaving-fluid temperature.
7) Evaporator and condenser pressure.
8) System refrigerant temperatures.
9) Chiller run hours.
10) Compressor run hours.
11) Compressor number of starts.
12) Compressor current.
13) Time of day:
a) Display module, in conjunction with
the microprocessor, must also be
capable of displaying the output
maintenance
I. Operating Characteristics:
J. Motors:
Condenser-fan motors shall be totally enclosed
single speed, 3-phase type with permanently lubri-
cated bearings and Class F insulation.
K. Electrical Requirements:
(results) of a service test. Service test
shall verify
switch, thermistor, fan, and com-
pressor before chiller is started.
b) Diagnostics shall include the ability
to review a list of the 30 most recent
alarms with clear language descrip-
tions of the alarm event. Display of
alarm codes without the ability for
clear language descriptions shall be
prohibited.
c) An alarm history buffer shall allow
the user to store no less than
30 alarm events with clear language
descriptions, time and date stamp
event entry.
d) The chiller controller shall include
multiple connection ports for com-
municating with the local equipment
network, the Carrier Comfort Net-
work (CCN) and the ability to access
all chiller control functions from any
point on the chiller.
e) The control system shall allow soft-
ware upgrade without the need for
new hardware modules.
4. Safeties:
a. Unit shall be equipped with thermistors and
all necessary components in conjunction
with the control system to provide the unit
with the following protections:
1) Loss of refrigerant charge.
2) Reverse rotation.
3) Low chilled fluid temperature.
4) Motor overtemperature.
5) High pressure.
6) Electrical overload.
7) Loss of phase.
b. Condenser fan motors shall have internal
overcurrent protection.
1. Unit shall be capable of starting and running at
outdoor ambient temperatures from 32 F (0° C)
to 125 F (52 C) for all sizes.
2. Unit shall be capable of starting up with 95 F
(35 C) entering fluid temperature to the cooler.
1. Unit primary electrical power supply shall enter
the unit at a single location (some chiller
voltage/size combinations require 2 power
supplies).
2. Primary electrical power supply shall be rated
to operate up to 125 F (52 C) ambient
temperature.
operation of every
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