Proportional Ssr Electric Heat; Start-Up, Operation; And Service; Start-Up - Carrier 35E Installation And Start-Up Instructions Manual

PROPORTIONAL (SSR) ELECTRIC HEAT
START-UP, OPERATION AND SERVICE
Proportional SSR Heat is an electronic, time-proportional
electric heat system. The heat output of the heater is modulated
utilizing quiet, rapid performing solid state relays. The relays
are switched off and on to allow the heating of electrical resis-
tance elements. The proportion of time the relay is on dictates
the proportion of maximum heat the electric heater can pro-
duce. The solid state relays are switched off and on by a sup-
plied Electric Heat Module (EHM). The EHM accepts an input
signal from the terminal unit controller or thermostat for the
amount of heat desired. The EHM can accept a variety of dif-
ferent input signals when interfacing with controls. The type of
input the EHM will accept is modified by changing the posi-
tion of one or two jumpers easily accessible on the board.
Proportional SSR Heat is available with an optional dis-
charge temperature sensor. When used with the discharge sen-
sor option, the Proportional SSR Heat system will modulate
outgoing temperature from the unit between the maximum
temperature setting and initial temperature of incoming air be-
fore heating began. The discharge temperature setpoint is
easily adjusted in the field by rotating the temperature dial on
the EHM. The EHM will not allow temperatures over the
APPLICATION
LX1 — On/Off
LX2 — 2 Stage (2Stg)
LX3 — 0-10V
LX4 — 2-10V
LX5 — Incremental (Incr)
LX6 — Binary (Bin)
LX7 — 3 Point Floating (Float)
Table 9 — Proportional SSR Heat Applications
DESCRIPTION
This application accepts one 24 Vac input at "Inc" to step the heater output
from OFF to 100% heater kW rating. The signal may be pulsed off and on
over a small time period to provide proportional heat. For example, a signal
that is on for 4.5 seconds every 10 seconds would produce 45% of the
heater's kW rating.
This two stage application accepts two 24 Vac inputs to step the heater
output from off to 50% or 100% heater kW rating. A signal to "Inc" is 50%
and a signal to "Dec" is 100%
This application accepts a 0-10 Vdc (0-20mA) signal to modulate the
heater output. The output is proportional to input signal (for example, 4.5
volts sets the heater to 45% of kW rating).
This application accepts a 2-10 Vdc (4-20 mA) signal to modulate the
heater output. The output is proportional to input voltage above 2 volts (for
example, 4.5 volts sets the heater to 25% of kW rating).
This application accepts one 24 Vac input to modulate heater output. An
increase signal will increase the heater output from 0% to 100% over a 4-
minute 15-second interval, staying at 100% afterward. When the signal is
removed, the heater output will decrease to 0% over the same time period.
This application mirrors a Normally
Closed hot water valve.
This application accepts two 24 Vac inputs to step the heater from off to
33%, 67%, or 100% of the heater's kW rating. A signal to "Inc" is 33%, a
signal to "Dec" is 67%, and a signal to both is 100%.
This floating input application accepts two 24 Vac inputs to increase or
decrease the heater output. As the increase signal is sent, the heater out-
put will increase from 0% to 100% over a 4-minute 15-second interval. If
the increase signal is removed, or a decrease signal is also added, the
heater output will stay constant at present point. When only the decrease
signal is received, the heater output will decline from the present level to
0% over the same time period. This application mirrors a three-point float-
ing hot water valve.
setpoint so as to prevent overheating, stratification, and energy
waste from heated air lost through overhead returns.
Units with Proportional SSR Heat use solid state relays,
which generate heat when used. The temperature of the
control box and/or heat sinks may be hot to the touch, caus-
ing personal injury.

Start-Up

INPUT SETTING — The Proportional SSR Heat board can
be controlled and operated in 7 different ways. The units are or-
dered with an LXY code, where X is coded for unit power and
Y is coded for the application (1-7). This Y application can be
changed in the field. The application desired is chosen by
placement of jumpers in the corner of board (see Fig. 14). The
jumper settings shown in Table 9 represent the pins at the bot-
tom corner of the control board as shown in Fig. 14. See Fig.
15-21 for application wiring diagrams.
16
WARNING
JUMPER SETTINGS