Quantech QCC2015CEE Installation, Operation And Maintenance Manual page 124

SECTION 7 – UNIT CONTROLS
A single system condensing unit MUST
have a jumper between terminals 13 - 17
on terminal block XTBC1. If the jumper
is not installed, the unit will act as a
2-system unit. The jumper is only checked
by the microboard at unit power-up. If
the jumper is removed, power must be
removed and re-applied to register the
change in memory.
N U M B E R O F
P E R S Y S T E M
The number of fans per system is programmed for the
total number of fans on each system, or the total num-
ber on the condensing unit divided by 2.
This MUST be programmed correctly to
ensure correct condensing unit operation.
S Y S X T R I P
U N I T T R I P
= X . X
Depending on the Current Feedback option, the trip
voltage for a specific system or unit high current trip
can be programmed. It also calibrates the current read-
out under the OPER DATA key. The approximate pro-
grammed value is calculated using the following for-
mulas:
460 VAC system trip volts
For individual system high current trip programming
on 460 VAC units:
• Add the sum of the compressor and fan RLA's in
the system
• Multiply the sum by 1.25
• Divide by 225 A
• The resulting voltage is the value that should be
programmed
124
F A N S
= X
V O L T S
= X . X V O L T S
V O L T S
V O L T S
For example, if fan and compressor RLA's total 100A:
5V x 100A
x 1.25
225A
The programmed value will be 2.8 V. A similar calcula-
tion and programming will be necessary for the other
system in a 2-system unit.
460 VAC unit trip volts
For total unit high current trip programming on
460 VAC units:
• Add the sum of all the compressor and fan RLA's
in the unit
• Multiply the sum by 1.25
• Divide by 225 A
• The resulting voltage is the value that should be
programmed
For example, if fan and compressor RLA's total 180A:
5V x 180A
x 1.25
225A
The programmed value will be 5.0V.
208/230 VAC units
On 208/230 VAC units, the process is similar, but
instead of performing the calculation using 225 A, a
number of 450 A must be substituted.
R E M O T E
P R O G R A M M E D
When communications is required with a BAS or Op-
tiView Panel, individual unit IDs are necessary for
communications with specific units on a single RS-485
line. ID 0-7 is selectable.
Form QCC2-NM1
Issue Date: 5/20/2021
625VA
= = 2.8V
225A
1125VA
= = 5.0V
225A
U N I T I D
= X
QUANTECH