Carrier 50KC*A/B0 Series, Installation Instructions Manual

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Fig. 52 — EconoMi$er IV
®
Wiring
Step 12 — Adjust Factory-Installed Options
SMOKE DETECTORS
Smoke detector(s) will be connected at the Controls Connec-
tions Board, at terminals marked “Smoke Shutdown”. Cut
jumper JMP 3 when ready to energize unit.
ECONOMI$ER IV OCCUPANCY SWITCH
Refer to Fig. 52 for general EconoMi$er IV wiring. External
occupancy control is managed through a connection on the
Controls Connections Board.
If external occupancy control is desired, connect a time clock
or remotely controlled switch (closed for Occupied, open for
Unoccupied sequence) at terminals marked OCCUPANCY.
Cut jumper JMP 2 to complete the installation.
Step 13 — Install Accessories
Available accessories include:
• Curb
• Thru-base connection kit (must be installed before unit is
set on curb)
• Electric heaters and single-point connection kits
• Manual outside air damper
• Two-Position motorized outside air damper
• EconoMi$er IV (with control)
• EconoMi$er2 (without control/for external signal)
• Power Exhaust
• Differential dry-bulb sensor (EconoMi$er IV)
• Outdoor enthalpy sensor
• Differential enthalpy sensor
• CO
2
sensor
• DDC interface (PremierLink™)
• Louvered hail guard
• Motormaster
® head pressure controls
• Phase monitor control
Refer to separate installation instructions for information on
installing these accessories.
Step 14 — Check Belt Tension
Measure the belt span length as shown in Fig. 53. Calculate
the required deflection by multiplying the belt span length by
1 /
64
. For example, if the belt span length is 32 inches: 32
x 1 /
64
= 1 /
2
-in. deflection.
BELT FORCE — DEFLECTION METHOD
Check the belt tension with a spring-force belt force deflec-
tion gauge (available from drive belt manufacturer).
1. Place a straightedge along the belt between the two pul-
leys. Measure the distance between the motor shaft and
the blower shaft.
2. Set the tension gauge to the desired tension (see Table 1
in Fig. 53). Place the large O-ring at that point.
3. Press the tension checker downward on the belt until the
large O-ring is at the bottom of the straightedge.
4. Adjust the belt tension as needed.
Adjust belt tension by loosing the motor mounting plate front
bolts and rear bolt (see Fig. 54) and slide the plate towards the
fan (to reduce tension) or away from the fan (to increase ten-
sion). Ensure the blower shaft and motor shaft are parallel to
each other (pulleys aligned). Tighten all bolts securely when
finished.