Carrier 50EJQ Installation, Start-Up And Service Instructions Manual page 13

LEGEND
FLA — Full Load Amps
HACR — Heating, Air Conditioning and
Refrigeration
IFM — Indoor Fan Motor
LRA — Locked Rotor Amps
MCA — Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection
NEC — National Electrical Code
OFM — Outdoor Fan Motor
RLA — Rated Load Amps
*Heater capacity (kW) is based on heater voltage of 208 v, 240 v, and
480 v. If power distribution voltage to unit varies from rated heater
voltage, heater kW will vary accordingly. Electric heaters rated at
54 and 72 kW are not available for 208/230 v, 50EWQ units.
†Fuse or HACR circuit breaker.
Bold indicates not available on 50EWQ units.
NOTES:
1. In compliance with NEC requirements for multimotor and combi-
nation load equipment (refer to NEC Articles 430 and 440), the
overcurrent protective device for the unit shall be fuse or HACR
breaker. The Canadian units may be fuse or circuit breaker.
2. Unbalanced 3-Phase Supply Voltage
Never operate a motor where a phase imbalance in supply voltage
is greater than 2%. Use the following formula to determine the per-
cent of voltage imbalance.
% Voltage Imbalance
max voltage deviation from average voltage
= 100 x
average voltage
NOTE: Sensor part numbers are as follows:
T-55 — CEC0121448-01
T-56 — CEC0121503-01
Fig. 14 — Field Control Temperature
Sensor Wiring
Service Tool, Building Supervisor, and ComfortWorks™ Soft-
ware — Access to the control board can be achieved through
the terminal marked CCN via a 3-wire bus.
IMPORTANT: Default bus address is 0. Default ele-
ment number is 1. Refer to CCN literature for infor-
mation on network addressing or changing CCN
communication defaults.
Carrier Comfort Network Interface — The 50EJQ,EWQ units
can be connected to the CCN. The communication bus wir-
ing is supplied and installed in the field. Wiring consists of
shielded, 3-conductor cable with drain wire.
The system elements are connected to the communication
bus in a daisy chain arrangement. The positive pin of each
system element communication connector must be wired to
the positive pins of the system element on either side of it,
LEGEND AND NOTES FOR TABLE 4
EXAMPLE: Supply voltage is 460-3-60.
Determine maximum deviation from average voltage.
Maximum deviation is 7 v.
Determine percent of voltage imbalance.
This amount of phase imbalance is satisfactory as it is below the
maximum allowable 2%.
3. MCA calculation for units with electric heaters over 50 kW =
(1.25 x IFM amps) + (1.00 x heater FLA).
the negative pins must be wired to the negative pins, and the
signal pins must be wired to signal ground pins. Wiring con-
nections for CCN should be made at the 3-pin plug (CCN
located at the base board). Consult CCN literature for fur-
ther information.
Conductors and drain wire must be 20 AWG minimum
stranded, tinned copper. Individual conductors must be
insulated with PVC, PVC/nylon, vinyl, Teflon, or polyeth-
ylene. An aluminum/polyester 100% foil shield and an outer
jacket of PVC, PVC/nylon, chrome vinyl, or Teflon with a
minimum operating temperature range of −4 F to 140 F is
required. Table 5 lists cables that meet the requirements.
IMPORTANT: When connecting the CCN communi-
cation bus to a system element, use a color coding sys-
tem for the entire network to simplify installation and
checkout. See Table 6.
Positive (+)
Negative (−)
NOTE: If a cable with a different color scheme is selected,
a similar color code should be adopted for the entire network.
At each system element, the shields of the communica-
tion bus cables must be tied together. If the communication
13
AB = 452 v
BC = 464 v
AC = 455 v
Average Voltage =
(AB) 457 − 452 = 5 v
(BC) 464 − 457 = 7 v
(AC) 457 − 455 = 2 v
% Voltage Imbalance = 100 x
= 1.53%
IMPORTANT: If the supply voltage phase imbalance is more than
2%, contact your local electric utility company immediately.
Table 5 — CCN Connection Approved
Shielded Cables
MANUFACTURER
Alpha
American
Belden
Columbia
Table 6 — Color Code Recommendations
SIGNAL CCN BUS CONDUCTOR
TYPE INSULATION COLOR
RED
Ground WHITE
BLACK
452 + 464 + 455
3
1371
=
3
= 457
7
457
CABLE PART NO.
2413 or 5463
A22503
8772
02525
CCN PLUG
PIN NO.
1
2
3