Carrier 38AQS008-012 User manual

38AK,38AKS,38AQS008-012
48/50H J,48/50TJ,50LJQ008-014
Accessory Low Ambient Operation
Motormaster ill Control Package
50/60 Hz
Installation Instructions
Part Numbers: CAMOTOR3001A00, CAMOTOR30Q2AOO
CONTENTS
Page
SAFETY CONSIDERATIONS. 1
GENERAL . 1,2
INSTALLATION. 2 -16
Step 1 — Install Motor .2
Step 2 — Install Motormaster III
Controller . 3
Step 3 — Install Sensor . 3
Step 4 — Make Electrical Connections . 6
Step 5 — Install Field-Fabricated
Wind Baffles and Brackets. 6
Step 6 — Restore Power to Unit. 6
TROUBLESHOOTING . 17
SAFETY CONSIDERATIONS
Installation, start-up, and servicing of this equipment
can be hazardous due to system pressures, electrical com¬
ponents, and equipment location (roofs, elevated struc¬
tures, etc.).
Only trained, qualified installers and service technicians
should install, start up, and service this equipment.
When working on this equipment, observe precautions in
the literature and on tags, stickers, and labels attached to
the equipment and any other safety precautions that may
apply.
A WARNING
Open all remote disconnects before servicing this equip¬
ment. Electrical shock could result in personal injury.
GENERAL
This book contains instructions for the installation,
start-up, and service of the Motormaster III control on
38AKS008-012, 38AQS008, 38AK008-012, 48/50TJ008-
014, 48/50HJ008-014, and 50LJQ008,012 units. The
Motormaster III control is not used on 50-Hz versions of
the 50HJ008-014 and 50LJQ008,012 units.
NOTE: The Motormaster III control is not used on 48/50HJ
and 48/50TJ units with 2 condenser fans. The control is
used on single condensing fan units only.
The Motormaster III accessory is UL (Underwriters’ Lab¬
oratories) and CSA (Canadian Standards Association)
approved on all split system and small rooftop electric cool¬
ing and gas heating/electric cooling units.
The Motormaster III device is a motor speed control de¬
vice which adjusts condenser fan motor speed in response
to declining liquid temperatures. A properly applied Motor-
master III control extends the operating range of air condi¬
tioning systems and permits operation at lower outdoor am¬
bient temperatures.
Table 1 shows the ambient temperature in cooling at which
each unit will operate without modification.
Table 1 — Unit Ambient Temperature Operation
UNIT
COMPRESSOR
CAPACITY
CONDENSER
TEMP
F (C)
MINIMUM
OUTDOOR
TEMP
F (C)
Small Rooftop Units
All
100 %
90 ( 32 )
25 (- 4 )
Split System Units
38AQS008 (60 Hz) 100 %
90 ( 32 )
55 ( 1 3 )
38AK/AKS0Q8
(50/60 Hz)
100 %
60 ( 1 5 )
38AKS009 (60 Hz) 100 %
■ ■
■ HEEHI
38AKS009 (50 Hz) 100 %
MEEl&En
in iitMM
38AKS012*
100 %
111 M\ |M|
(50/60 Hz)
67 %
■ Eiiigm
M II 1 HIM
38AK012
(50/60 Hz)
100 %
52 ( 1 1 )
* Unit has one step of unloading.
To operate the units below the ambient temperatures in
Table 1, wind baffles and the Motormaster III control pack¬
age must be added. The Motormaster III control permits
operation of the unit to an ambient temperature of -20 F
(-29 C) for small rooftop units, and 0 F (-18 C) for split
system units.
The Motormaster III regulates the speed of 3-phase fan
motors which are compatible with the control. These
motors are included in the package. See Tables 2 and 3 for
the contents of the Motormaster III accessory packages.
The CAMOTOR3001A00 package contains a motor for
208/230 volt, 60 Hz and 220 volt, 50 Hz applications. The
CAMOTOR3002A00 package contains a motor for 460
and 575 volt, 60 Hz and 400 volt, 50 Hz applications. See
Fig. 1.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book|1 |1 |1 |1 |4 [4 |4 |4 PC 111 Catalog No 533-803 Printed in U S A. Form 38/48/50-4SI Pg 1 1-95 Replaces: New

Table 2 — Motormaster® III Control Package
CAMOTOR3001A00, 208/230 v, 60 Hz and 220 v,
50 Hz Applications
QUANTITY
ITEM
PART NO.
1
Motormaster III Control
HR46GN001
1
Sensor
30GT412176
1
Motor
HD52GK208
8
Screw (5/16-in.)
AL81AS216
1
Relay
HN61KZ024
2
Screw (no. 6 — 20 x 3/4-in )
AL56AU128
1
Bracket
50DK507132
1 Socket
HY07RB030
Table 3 — Motormaster III Control Package
CAMOTOR3002A00, 460 and 575 v, 60 Hz and
400 v, 50 Hz Applications
QUANTITY
ITEM
PART NO.
1 Motormaster III Control
HR46GN001
1 Sensor
30GT412176
1
Motor
HD52GK460
8
Screw (5/16-in )
AL81AS216
1 Relay
HN61KZ024
2
Screw (no. 6 — 20 x 3/4-in.)
AL56AU128
1
Bracket
50DK507132
1 Socket
HY07RB030
Before Installing — Inspect the contents of the acces¬
sory package before installing. File a claim with the ship¬
per if shipping damage is found. Contact the Carrier dis¬
tributor if a part is missing.
Fig. 1 — Motormaster III Control
INSTALLATION
Step 1 — Install Motor
A WARNING
To avoid the possibility of electrical shock, open all
disconnects before installing or servicing this
acc essory. _
1. Shut off unit power supply.
2. Remove unit access panel and control box cover.
3. Disconnect fan motor connection in control box and
remove motor leads from control box.
4. Remove condenser fan assembly (grille, motor, motor
cover, and fan) by removing the 6 grille holddown screws.
5. Loosen fan hub set screws and remove condenser fan
from motor shaft.
6. Carefully lift off motor cover.
7. Remove the 4 holddown nuts that attach the motor to
the grille. Pull the motor wires through the grille
conduit.
8. Cut back the steel conduit on the grille (one grille wire
width) to allow adequate space for new fan motor.
9. Feed the Motormaster III motor wires through the con¬
duit and install motor from accessory kit onto grille us¬
ing nuts from Step 7.
10. Replace the motor cover on the grille using the square
cutouts.
11. Replace condenser fan on motor shaft.
12. Adjust fan height as shown in Fig. 2.
13. Tighten set screws on fan hub to 7 ft-lbs (9.52 N-m
[newton-meters]) ± 1 ft-lb (1.5 N-m).
NOTE: On 48HJ009 and 48HJ/TJ014 units, perform Step 2
— Install the Motormaster III Controller through Step 4 —
Make Electrical Connections, before reinstalling the con¬
denser fan. Motormaster III installation is done through the
condenser fan opening with the fan and motor removed.
14. Reinstall condenser fan assembly onto unit using screws
from Step 4. Torque to 20 in.-lbs (2260 mN-m)
± 2 in.-lbs (226 mN-m).
15. Pull motor wires completely through conduit.
MOTOR COVER OUTLET GRILLE
Fig. 2 - Condenser Fan Height Adjustment

Step 2 - Install Motormaster® III Controller
1. Configure the control signal selection switch. Remove
the cover of the Motormaster III control. Set the switch
on the Motormaster III control board (underneath cover)
to accept the thermistor (sensor) input signal. Set the
frequency switch to match the unit power supply (50 Hz
or 60 Hz). See Fig. 3 for switch locations and proper
position. Replace the cover.
2. 38AK008,012; 38AKS008-012; 48HJ008,012; 48TJ008-
012; 50HJ/TJ008-014; AND 50LIQ008,012; UNITS WITH
SINGLE POINT BOX: Mount the Motormaster III con¬
troller on the unit in the location specified in Fig. 4-6.
The controller must be mounted vertically with the leads
at the bottom. Using the template provided on the last
page of the book, mark the 4 mounting hole locations.
Mount the controller using the 5 /i6-in. self-drilling screws
provided.
, A CAUTION
To avoid damaging components and wiring, use ex¬
treme care when drilling screw holes and screwing
in fasteners.
50HJ/TJ008-014 AND 50LJQ008,012 UNITS WITH¬
OUT SINGLE POINT BOX; 48HJ009 (208/230
AND 460 V); AND 48HJ/TJ014 UNITS: Mount the
Motormaster III controller on the unit in the location spec¬
ified in Fig. 7 and 8. The controller must be mounted
vertically with the leads at the bottom. Using the tem¬
plate supplied on the last page of the manual, mark the
4 mounting locations. Mount the controller using the
5 /i6-in. self-drilling screws provided. To prevent any
water leakage though the bulkhead (the partition sepa¬
rating the indoor and outdoor sections), an electric
component compatible, general purpose silicon rubber
sealant must be used along the 4 edges of the controller
and at the 4 mounting-screw locations.
38AQS008 AND 48HJ009 (575 V) UNITS: The
Motormaster III controller must be mounted on a sheet
metal bracket provided. Mount the bracket on the unit
in the location specified in Fig. 9 and 10 using four
5 /i6-in. self-drilling screws provided. If needed, a bracket
mounting template is provided on page 21. The control¬
ler must be mounted vertically, with the leads at the
bottom. Mount the controller on the bracket using the
remaining four 5/16-in. self-drilling screws. See Fig. 11
for controller mounting details.
Step 3 — Install Sensor
38AK008,012; 38AKS008-012 AND 48/50HJ,TJ008-014
UNITS — Install the sensor for thermistor input control on
the header tube designated in Fig. 12. Connect the sensor
leads to the violet and gray control signal leads on the
Motormaster III controller. Wrap and tie excess sensor wir¬
ing. Refer to Step 4 — Make Electrical Connections and
the unit wiring diagram for more information on wiring the
sensor.
A CAUTION
Sensor assembly is delicate. Handle with care.
38AQS008 AND 50LJQ008,012 UNITS - Wiring is field-
supplied. Wiring must be 16 AWG (American Wire Gage)
(1.5 mm 2 ), appliance wiring material, rated 75 C or its equiv¬
alent, with 2 ?64-in. (.8 mm) minimum insulation thickness.
All wiring must comply with NEC (National Electrical Code)
and applicable local codes.
n izzi
□ □
□ cz=]
(SENSOR) THERMISTOR* 4 - 20mA
50 HZ PHASE SEQUENCE
a INDICATOR
|fl| ' ^ ADJUST SWITCH
Pi TO MATCH LINE
T FREQUENCY
60 HZ
ADJUST SWITCH TO
MATCH INPUT
CONTROL SIGNAL
CONT ROL I N P U T
_r*n_
LEADS TO POWER
SOURCE
LEADS TO
MOTOR
BLACK LI
BLUE L3 -
YEL L2
GRN (GND) |
CONTROL
SIGNAL
LEADS
+VIO
-GRAY
3 HOLES 0 88 DIA (FOR 1/2 IN CONDUIT)
LEGEND
GND — Ground
*For thermistor (sensor) signal, move switch to the left.
NOTE: Thermistor is designated in text as “sensor.”
Fig. 3 - Motormaster III Control Signal Selection Switch
3

ACCESS PANEL
Fig. 4 — Motormaster® III Controller Location —
38AK, 38AKS Units
Fig. 5 — Motormaster III Controller Location —
50HJ,50LJQ,50TJ008-014
(With Single Point Box)
MOTORMASTER III
COND. COIL \
Fig. 6 — Motormaster III Controller Location —
48HJ/TJ008, 48TJ009, 48HJ/TJ012
Fig. 7 - Motormaster III Controller Location -
50HJ, 50LJQ, 50TJ008-014 (Without Single Point Box)
4
ACCESS
PANEL

TOP VIEW
Fig. 8 — Motormaster® III Controller Location —
48HJ,TJ014, All Voltages; 48HJ009, 208/230,
460-3-60 Only
TOP VIEW
Fig. 9 — Motormaster III Controller Location —
48HJ009 (575 V)
Fig. 10 — Motormaster III Controller Location —
38AQS008
TOP VIEW
d
_ I
m
o
o
o
o
SIDE VIEW FRONT VIEW
Fig. 11 — Motormaster III Controller Mounting
5

Install the sensor for thermistor input control on the header
tube designated in Fig. 13 and 14. Insert relay into socket.
Install the Motormaster® III relay in the unit control box,
in the location specified in Fig. 15 and 16. Use the two
no. 6-20 x 3/4-in. screws provided.
Connect one sensor lead to the violet control signal lead
on the Motormaster III controller and to a field-supplied
16 AWG wire with a wirenut. Connect the remaining
sensor lead to the gray control sensor lead on the
Motormaster III controller and to another field-supplied
16 AWG wire with a wirenut.
Route both field-supplied wires through a factory-
punched access hole under the control box. Attach the wires
to screw terminals 1 and 9 on the Motormaster III relay in
the control box. Wrap and tie excess sensor wiring. Wrap
wirenuts with waterproof tape to prevent them from loos¬
ening and to ensure watertightness. Refer to Step 4 - Make
Electrical Connections and the unit wiring diagram for more
information on wiring the sensor.
A CAUTION
Sensor assembly is delicate. Handle with care.
Step 4 — Make Electrical Connections
A WARNING
To avoid possibility of electrical shock and personal
injury, turn off all power to unit before making elec¬
trical connections. Tag all disconnects to alert others
not to turn on power until work is completed.
The wires necessary for wiring the Motormaster III con¬
trol to the unit must be field-supplied. Use 16 AWG (Amer¬
ican Wire Gage) (1.5 mm 2 ) appliance material wire, with
2/64-in. (.8 mm) minimum insulation thickness. Use 75 C
type or equivalent. All wiring must comply with NEC
(National Electrical Code) and applicable local codes.
38AK008,012 AND 38AKS008-012 UNITS - Power wir¬
ing must comply with all local and national electrical code
(NEC) requirements. Refer to Fig. 17-19 for power wiring
connections. Utilize field-supplied wirenuts and l A in.
insulated female quick-connects for making power wiring
connections. Wrap wirenuts with waterproof tape to pre¬
vent them from loosening and ensure watertightness.
NOTES:
1. On 50 Hz units, disconnect the yellow wire connected
to terminal 22 of the compressor contactor (C).
2. See wiring diagram on unit for more details.
48/50HJ008-014 AND 48/50TJ008-014 UNITS - Power
wiring must comply with all local and National Electrical
Code (NEC) requirements. Refer to Fig. 20-25 for power
wiring connections. Utilize field-supplied wirenuts and
V4-in. insulated female quick-connects for making power
wiring connections. Wrap wirenuts with waterproof tape to
prevent them from loosening and ensure watertightness.
NOTES:
1. On 220 v, 50 Hz units, disconnect the black wire con¬
nected to capacitor 1. On 400 v, 50 Hz units, disconnect
blue wire connected to capacitor 1. Cap wire with a wire¬
nut (50TJ008-014 only).
2. See wiring diagram on unit for more details.
38AQS008 AND 50LJQ008,012 UNITS - Power wiring
must comply with all local and National Electrical Code
(NEC) requirements. Refer to Fig. 26-28 for power wiring
connections. Utilize field-supplied wirenuts and V4-in. in¬
sulated female quick-connects for making power wiring con¬
nections. Wrap wirenuts with waterproof tape to prevent
them from loosening and ensure watertightness. See wiring
diagram on unit for more details.
Step 5 - Install Field-Fabricated Wind Baffles
and Brackets
A WARNING
To avoid the possibility of electrical shock, open
all disconnects before installing or servicing this
accessory.
Wind baffles must be field-fabricated for all units to en¬
sure proper cooling cycle operation at low-ambient temper¬
atures with Motormaster III controls. See Fig. 29 and 30
for number and sizes of baffles required and for baffle de¬
tails. Use 20-gage (1 mm) galvanized sheet metal or similar
corrosion-resistant material for the baffles. Use field-
supplied screws to attach baffles to unit. Screws should be
14-in. (6.3 mm) diameter or larger. Drill required screws
holes for mounting the baffles.
A CAUTION
To avoid damage to refrigerant coils and electrical com¬
ponents, use extreme care when drilling screw holes
and screwing in fasteners.
Step 6 — Restore Power To Unit - When all elec¬
trical connections have been made, ensure they are tight
and correct.
1. Restore power to the unit.
2. Check the phase sequence indicator on the Motormaster
III control. It should not be lit. If lit, turn off power and
reverse LI (black) and L2 (yellow) power leads. See
Fig. 3.
3. With phasing on Motormaster III control correct,
make sure that the fan motors are rotating in the
proper direction. If fan rotation is backwards, shut off
power. Reverse the supply power leads between the
Motormaster III control and the condenser fan motor to
correct rotation.
4. Reinstall control box cover.
5. Reinstall unit access panel.
6

Fig. 13 — Motormaster® III Sensor Locations — 38AQS Units
1
jSENSOR
LOCATION
J
RETURN BEND END
50LJQ008
RETURN BEND END
50LJQ012
Fiq. 14 — Motormaster III Sensor Locations — 50LJQ Units

MOTORMASTER III RELAY
Fig. 15 — Motormaster® III Relay Location —
38AQS008
MOTORMASTER III RELAY
Fig. 16 - Motormaster III Relay Location
50LJQ008,012
Fig. 17 - Fan Power Wiring - 38AKS009,012 - 208/230 V, 460 V; 60 Hz and 220 V, 400 V; 50 Hz
LEGEND
C — Compressor Contactor
MMSN - Motormaster Sensor
OFM — Outdoor-Fan Motor
NOTES:
1. On 50 Hz units, disconnect yellow wire connected to Termi¬
nal 22 of the compressor contactor (C). Tape wire and se¬
cure inside control box.
2. See wiring label on unit for more details
Fig. 18 - Fan Power Wiring - 38AK008,012; 38AKS008 -208/230 V, 460 V; 60 Hz and 220 V, 400 V; 50 Hz
10

LEGEND
MMSN — Motormaster® Sensor
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
TB2 — Terminal Block 2
NOTE: See wiring label on unit for more details
BLK"
- GRA —
VIO
MOTORMASTER
.111
CONTROLLER
—I
MMSN
RED
ORN
BRN
Fig. 19 - Fan Power Wiring - 38AK008,012; 38AKS008,009,012 - 575 V; 60 Hz
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
NOTE: See wiring label on unit for more details
Fig. 20 - Fan Power Wiring - 50HJ008-012 - 208/230 V; 60 Hz, 50HJ008-014 - 460 V; 60 Hz,
and 50TJ014 - 460 V; 60 Hz
IFC — Indoor-Fan Contactor
MMSN — Motormaster Sensor
OFM — Outdoor-Fan Motor
NOTE: See wiring label on unit for more details.
Fig. 21 - Fan Power Wiring - 48/50TJ008-012 - 208/230 V and 460 V; 60 Hz
11
.il-O
"1-0
"K3

C2
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
NOTE. See wiring label on unit for more details.
Fig. 22 - Fan Power Wiring - 50HJ014; 50TJ014 - 208/230 V; 60 Hz
IFC — Indoor-Fan Contactor
MMSN — Motormaster Sensor
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
NOTE: See wiring label on unit for more details
Fig. 23 - Fan Power Wiring 48HJ008-014; 48TJ014 - 208/230 V and 460 V; 60 Hz
'V
YEL
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
TB3 — Terminal Block No. 3
NOTE: See wiring label on unit for more details
Fig. 24 — Fan Power Wiring — 48/50HJ,TJ008-014 - 575 V; 60 Hz
12
0
-
1
"

Cl — Compressor Contactor No. 1
MMSN — Motormaster® Sensor
OFM — Outdoor-Fan Motor
NOTES:
1. Disconnect black wire on 220-v units and blue wire on 400-v
units connected to capacitor no. 1. Cap with wirenut.
2. See wiring label on unit for more details.
Fig. 25 — Fan Power Wiring — 50TJ008-014 — 220 V and 400 V; 50 Hz
LEGEND
C — Compressor Contactor
MMR — Motormaster Relay
MMSN — Motormaster Sensor
OFC — Outdoor-Fan Contactor
OFM — Outdoor-Fan Motor
NOTE: See wiring label on unit for more details.
Fig. 26 — Fan Control/Power Wiring — 38AQS008 — 208/230 V and 460 V; 60 Hz
13
0-111
GH"

GRA
VIO
MOTORMASTER
m
CONTROLLER
POWER WIRING
CONNECTION BOARD
^ (INSIDE CONTROL BOX)
BLU —
WHT
BRN
LEGEND
Indoor-Fan Contactor
Motormaster® III Relay
Motormaster Sensor
Outdoor-Fan Contactor
Outdoor-Fan Motor
OFM
GRN-YEL-
-9
IFC
MMR
MMSN
OFC
OFM
NOTE: See wiring label on unit for more details
CONTROL WIRING
Fig. 27 — Fan Control/Power Wiring — 50LJQ008-012 — 208/230 V and 460 V; 60 Hz
MMR
Fig. 28 - Fan Control/Power Wiring - 50LJQ008-012 - 575 V; 60 Hz
14
c
v

LEFT
REAR
DIMENSIONS (in.) DIMENSIONS (mm)
LEFT BAFFLE LEFT BAFFLE
UNIT
38
A
B
C
D E F G H
■ UNIT
1 38
A B
C D
E
F
G
H
1
AK008;
AKS008-012;
AQS008
283/4
29 5 /s 30V2 35
2
~
10
18
26
34
akoo8;
AKS008-012;
AQS008
730
752 775
889
51 254 457
660
864
AK012
283/4 29% 30Y 2
”35“
10 18
~26~
34
AK012
730
752 775
889 51
254 457
660
864
REAR BAFFLE REAR BAFFLE
UNIT
38
A
B
C
D E F G H
, UNIT
1 38
A
B
C
D
E
F G H
1
akoo8;
AKS008-012;
AQS008
36V2
373/8
38V4
35 2
10
18
26
34
akoo8;
AKS008-012;
AQS008
927
949
972
889 51 254 457
660
864
AK012
36Y2
373/8
38V4
"35"
~
10 18
~26~
34 AK012
927
949
972
889
51
254 |
457
660
864
RIGHT BAFFLE RIGHT BAFFLE
UNIT
38
A
B
C
D E F G
H
, UNIT
1 38
A
B
C D
E
F
G
H
1
AK008;
AKS008-012;
AQS008
9 1 5 /16
10 1 3 /i6 irvie 35 2 10 18 26
34
AK008;
AKS008-012;
AQS008
252 275
297
889
51 254 457
660
864
AK012
197/8
20 3 A
21%
35 2
IcT
18
26
34
AK012 505
527 | 549
889 51 254
457
660
864
Fig. 29 - Wind Baffle Mounting Details, 38AK,AK$,AQS Units
15

UNIT
48/50HJ,TJ008,009;
50LJQ008
48/50HJ,TJ012,014;
50LJQ012
! B
c
D
[ E
G
H
22 V 4
30 V 2
22V 4 30V 2
48/50HJ,TJ008,009;
50LJQ008 _
48/50H J,TJ012,014;
50LJQ012
DIMENSIONS (mm)
1134.0 894.0 150.0
1134.0 1098.0 150.0
G
H
566 0 774 0
566.0
774.0
48/50HJ008 _
48/50HJ009; 48/50TJ008;
50LJQ008
48/50TJ009 _
48/50TJ012
48/50HJ012,014; 48/50TJ014;
50LJQ012
UNIT
48/50HJ008 _
48/50HJ009; 48/50TJ008;
50LJQ008 _
48/50TJ009 _
48/50TJ012
48/50HJ012,014; 48/50TJ014;
50LJQ012
FRONT BAFFLE
DIMENSIONS (in)
A
B C D
31%
32V 2
33V4
35V4
41 5 /e
423/8
43 Ve
35V 4
16%
17% 18 Vs 35V4
26% 27%
28 Va
43V4
41%
42%
43 Ve
43V 4
DIMENSIONS (mm)
.6 844.8
6 844.8
.6 844 8
.6
844 8
6
844.8
Fig. 30 - Wind Baffle Mounting Details, 48/50HJ,TJ008-014; 50LJQ008,012
16

TROUBLESHOOTING
1. The Motormaster® III control must be securely grounded
to the cabinet of the unit to function properly.
2. The power frequency switch must be in the correct
position for the power supply being used. The control
switch must be set at the thermistor setting.
3. Motormaster III controls may be applied only to spe¬
cially qualified fan motors. Ensure that the proper fan
motor has been installed with the Motormaster III con¬
trol. See Tables 2 and 3.
4. A true RMS (Root Mean Square) meter is required to
accurately read the output from the Motormaster III
control because of the electronically controlled output
voltage.
5. T hermistor sensor lead connections should be carefully
rechecked if there is an operational problem. See the
thermistor characteristic for sensor 30GT412176 shown
in Fig. 31. The controller operates between 1600 ohms
and 5800 ohms. At 1600 ohms the controller is at full
voltage. At 5800 ohms the output is at a minimum (10%
of motor speed).
i—-1-1-1-1-1-1-—i
15 20 25 30 35 40 45
TEMPERATURE (C)
LEGEND
|Tolerance band for allowable Motormaster III resistance values.
Fig. 31 - Thermistor Resistance vs Temperature
50
17

Copyright 1995 Carrier Corporation
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
1 1
4
4
4
4 PC 111 Catalog No 533-803 Printed in U S.A. Form 38/48/50-4SI Pg 18 1-95 Replaces: New
Tab
la
1b
3a 5a 2a 5a 6a
6b

0.130"(3.3mm ) n . .
0.134"(3.4mm) U 1 A
(6 PLACES TYPICAL)