22
Figure 9. Dryer Interconnection Schematic
Figure 8. Typical Clothes Dryer Interconnection
14.4
Turn off breaker. Remove one of the two wires from the
dryer and cap with wirenut. Turn on breaker. Turn on
dryer and suspend this wire such that it will not short
to anything. Turn on dryer to see if the motor starts. If
so, this is the correct wire to attach to the power relay.
To verify this, turn off breaker, reattach this wire to the
breaker and remove the other wire from the breaker. Turn
on breaker. Start the dryer again and this time the dryer's
motor should not start. If it does, (dryer starts with either
wire disconnected) your dryer may require some internal
wiring modifications before it can be connected to the
load controller. Contact the dryer manufacturer or consult
the dryer 's wiring diagram.
14.5
Turn off dryer breaker. Remove the proper wire from the
breaker (with the proper wire removed, the dryer motor
should start). Run two lengths of #10 AWG wire
between the breaker panel and the relay unit. Wire-nut
the disconnected length of wire to one of the lengths of
wire in the breaker panel. Wire-nut the other end of this
wire to one red lead of the relay's contact. From the
relay's other red lead of the contact, wire-nut this to the
other short length of wire that returns into the breaker
panel. Connect the other end of the wire back to the
dryer's circuit breaker panel as shown in Figure 9.
15.3 Connecting Demand
Controller to an Electric
Furnace
When connecting an electric furnace to the demand
controller, the simplest, most economical method is to
install a remote relay box at the furnace. This relay box
usually contains 3 to 6 relays for connection to each
individual heat strip in the furnace. These relays are
connected to the main relay unit by means of a multicon-
ductor cable, normally one pair per relay. For example, for
4 remote relays, a #18 AWG eight conductor cable is
required. Twisted pair or color coded wire is recom-
mended for this application for convenience. Relay
connector pigtails (optional) should be used with the unit
for connection at the main relay unit to the multi-conduc-
tor cable. At the remote relay unit, relay leads are wire-
nutted to the multiconductor cable as shown in Figure 11.
15.3.1
15.3.1
15.3.1
15.3.1
15.3.1
Determine the staging sequence of the electric furnace.
For example, many furnaces have 3 stages of heat. Stage
#1 consists of two 5 KW heating elements. Stage #2
many times also consists of two 5 KW heating elements
and Stage #3 has one 5 KW heating element.
Figure 10. Typical Low Voltage Load
Interconnection
15.0 Wiring Power
Relays to Heat Pumps
and Air Conditioners
15.1
Turn off breakers of loads which are going to be con-
nected to the controller.
15.2
Connecting air conditioners and/or heat pump compres-
sors to the Energy Sentry
unit is normally accomplished
by inserting a relay in series with the low voltage 24
VAC thermostat control loop as shown in Figure 10
(generalized drawing).
BREAKER
120V N 120V
POWER RELAY
M
CLOTHES
DRYER
TEST: DRYER STARTS WITH RELAY OPEN
ELEMEN
NEUTRAL
TO DRYER
30A
BREAKER
BREAKER
PANEL
/LOAD
CENTER
RELAY UNIT
RELAY
STAT
THERMO-
LOAD
24 VAC
120V N 120V
BREAKER
AIR CONDITIONER / HEAT PUMP
LOW VOLTAGE RELAY
