29
5-572.10
(40) Motor Starter – (OPT)
The motor starter is factory installed in the blower electrical
section. A motor starter is required for:
•
All three phase motors
•
Single phase motors 1-1/2 Hp and greater
If the factory installed motor starter option was not ordered with
a unit that requires it, a motor starter must be field supplied and
installed. Alternatively for three phase motors, see also the
Variable Frequency Drive option below.
The overload module of the motor starter is designed to protect
the motor from exceeding the nameplate amps. If the motor
exceeds the amp draw on the current set point dial, the trip
condition is indicated by a red color in the trip indicator window.
The current set point dial is factory set to the motor full load
amps listed on the motor nameplate.
The motor starter can be placed in the automatic or manual
reset positions. Automatic reset is accomplished by depressing
the “RESET” button and turning the button 1/4 turn. When in
the automatic reset position, if the overload module trips, the
module will reset itself once the overload relay has cooled.
In the manual reset position, if the overload module trips, the
“RESET” button must be depressed before the blower can
operate.
The contactor module includes one (1) normally open auxiliary
contact. The contact rating is 10 amps.
RESET
WINDOW
INDICATOR
TRIP
DIAL
SET POINT
CURRENT
H
A RE
S
E
T
NC
NO
96
95
97
98
T3
6
T2
4
T1
2
A2
14
NO
6
T3
4
T2
T1
2
NO
13
L3
5
L2
3
A2
L1
1
A1
CONTACTOR
MODULE
OVERLOAD
MODULE
Figure 29.1 - Motor Starter
SYSTEM OVERRIDE SWITCH POSITIONS
DAMPERS ONLY
DAMPERS & BLOWER ONLY
DAMPERS, BLOWER & FURNACE ONLY
* RESET SWITCHES TO “OFF” POSITION AFTER TESTING
ON
OFF
OFF
ON
ON
OFF
ON
ON
ON
ON
OFF
OFF
OFF
ON
ON
5H0756370000 REV B
Figure 29.2 - Service Switches
(41) Mild Temperature Stat – (OPT) (All Except Digit 12=9)
The mild temperature thermostat is factory installed in the
blower electrical section. The mild temperature thermostat is
designed to lockout the burner during mild weather conditions
which prevents the burner from cycling. The thermostat must be
field set to the desired mild temperature condition (refer to the
latest revision of Modine Literature 75-540).
For units with the Modine Control System option (Model Digit
12=9), this feature is integral to the control logic and utilizes
existing sensors included with that option. Refer to the latest
revision of the Modine Control System Manual, literature 74-510
for additional information.
(42) Proportional Temperature Controller – (OPT
)
Refer to description for item # 40.
(43) Warm-Up Stat – (OPT) (All Except Model Digit 12=9)
A warm-up stat can be provided with Air Control options (Model
Digits 20-21=EA, GG, or GH) and factory installed in the blower
electrical section with the sensor in the return air stream. The
warm-up thermostat monitors the return air temperature upon
changing to the occupied mode and prevents the fresh air
dampers from opening until the temperature of the return air has
reached the desired set point (typically 65°F or 5°F below the
room temperature).
(44) Blower Supply Power Terminal Strip – (STD)
The terminal strip is labeled to match the electrical wiring
diagram provided with the unit. All field wiring connections
should be made to the bottom side of the terminals to prevent
miswiring by modifying the factory wiring which is made to the
top of the terminal strip.
(45) Service Switches – (OPT) (All Except Model Digit 12=9)
The service switches are factory installed in the blower electrical
section. The service switches allow for service personnel to
independently test operation of the damper, blower, and furnace
without using jumper wires. The switches override the remote
monitoring panel and/or thermostats to energize each compo-
nent directly. All switches need to be reset to the “OFF” position
after testing otherwise the components will remain energized.
For units with the Modine Control System option (Model Digit
12=9), this feature is integral to the control logic and provides
service personnel with real-time operating status of the unit
systems. Refer to the latest revision of the Modine Control
System Manual, literature 74-510 for additional information.
(40) Variable Frequency Drive – (OPT)
The VFD controller adjusts the motor rpm to vary the unit air
flow. The minimum air flow may be varied between 30 and
100% of the full speed air flow depending on the controls
selection of the unit (refer to the section "Variable Air Volume
Applications" on page 21 for additional information).
The control changeover options include two speed, building
pressure control, and building management control. For units
with the Modine Control System option (Model Digit 12=9),
additional control options may be available. Refer to the latest
revision of the Modine Control System Manual, literature 74-510
for additional information.
COMPONENT DESCRIPTIONS
