Carrier AQUAZONE VQL, Инструкция по установке, запуску и обслуживанию

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SUPPLY VOLTAGE — Operating voltage to unit must be
within voltage range indicated on unit nameplate.
On 3-phase units, voltages under load between phases must
be balanced within 2%. Use the following formula to deter-
mine the percentage voltage imbalance:
% Voltage Imbalance
Example: Supply voltage is 460-3-60.
AB = 452 volts
BC = 464 volts
AC = 455 volts
Determine maximum deviation from average voltage:
(AB) 457 – 452 = 5 v
(BC) 464 – 457 = 7 v
(AC) 457 – 455 = 2 v
Maximum deviation is 7 v.
Determine percent voltage imbalance.
= 1.53%
This amount of phase imbalance is satisfactory as it is
below the maximum allowable 2%.
Operation on improper line voltage or excessive phase
imbalance constitutes abuse and may cause damage to electri-
cal components.
NOTE: If more than 2% voltage imbalance is present, contact
local electric utility.
EXTERNAL LOOP POWER CONNECTION — If the unit
is to be connected to an external loop pump or flow controller,
connect the pump to the loop pump terminal block PB1. The
maximum power handling is 4 amps at 240 volts. The pumps
will automatically cycle as required by the unit.
208-VOLT OPERATION — All 208-240 volt units are factory
wired for 208 volts. The transformers may be switched to
240-volt operation (as illustrated on the wiring diagram) by
switching the red (208 volt) wire with the orange (240 volt)
wire at the L2 terminal.
AIRFLOW AND EXTERNAL STATIC PRESSURE —
The 50HQL,VQL units are available with standard, low, and
high static factory-installed options. These options will substi-
tute a different blower drive sheave for each static range. In
addition, certain static ranges may require the optional 3 hp fan
motor.
Sheave Adjustment — The 50HQL,VQL units are supplied
with a variable sheave drive on the fan motor to adjust for
differing airflows at various ESP (external static pressure) con-
ditions. See Tables 5A-5J for unit airflows. When fully closed,
the sheave will produce the highest static capability (higher
rpm). To adjust sheave position, follow the procedure outlined
below:
1. Loosen belt tension and remove belt.
2. Loosen set screw on fan motor.
3. Open sheave to desired position.
4. Retighten set screw and replace belt.
NOTE: Set belt tension as outlined below.
Belt Tension Adjustment — An overly loose belt will, upon
starting motor, produce a slippage “squeal” and cause prema-
ture belt failure and or intermittent airflow. An overly tight belt
can cause premature motor or blower bearing failure. To adjust
the belt tension, follow the procedure outlined below:
1. Remove belt from motor sheave.
2. Lift motor assembly.
3. Loosen the
5
/
16
-in. hex nuts on the grommet motor adjust-
ment bolts (2 per bolt). To increase the belt tension loosen
the top hex nut. To decrease the belt tension loosen the
bottom hex nut.
4. Turn the bolts by hand to the desired position then tighten
the
5
/
16
-in. hex nuts (2 per bolt).
5. Lower the motor assembly.
6. Install the belt.
7. The belt tension can be adjusted by using one of the fol-
lowing methods:
a. Tighten until belt deflects approximately 1 /
2
-in.
with very firm finger pressure.
b. Grasp belt midway between two pulleys and twist
for a 90 degree rotation.
NOTE: Adjusting less than 90 degrees will over-
tighten the belt and adjusting more than 90 degrees
will loosen belt.
c. Set proper belt tension to 70 to 80 lb.
NOTE: The motor position should not need adjustment. Motor
sheave position is at mid position of each sheave. For example,
the motor sheave is 2.5 turns open on a 5-turn sheave. The belt
tension adjustment can also be accomplished by turning the
5
/
16
-in. hex nuts to the desired position.
NOTE: Available airflows for all units are shown in
Tables 5A-5J.
= 100 x
max voltage deviation from average voltage
average voltage
Average Voltage =
452 + 464 + 455
3
=
1371
3
= 457
% Voltage Imbalance = 100 x
7
457