Install Instructions

Installation Instructions for
Models 50 and 51 Current Sensing Relays
Current Sensing Relays
GENERAL INFORMATION
MODEL 50 HUMIDIFIER WIRING DIAGRAMS
READ COMPLETE INSTALLATION INSTRUCTIONS BEFORE STARTING.
GENERAL INSTALLATION PROCEDURES FOR MODELS 50 AND 51 RELAYSMODELS 50 AND 51 RELAY
INSTALLED WITH MANUAL HUMIDIFIER CONTROL INSTALLED WITH AUTOMATIC HUMIDIFIER CONTROL
WARNING
120 volts may cause serious injury from electric shock.
Disconnect power to the furnace before attaching the
Model 50 or 51 Current Sensing Relays.
CAUTION
1. Load must not exceed recommended ratings. (See specifications)
2. Load must be wired in series with relay.
3. Do not power humidifier from furnace blower motor circuit.
1. Disconnect power before installing.
2. The Models 50 or 51 must be located at least 4” from any transformer.
3. Remove the screw from the bracket and place the common wire that will activate the relay
between the bracket and the plastic case.
4. If the current through the common wire is less than 4 amps, wrap it one or more additional
turns around the metal bracket.
5. Replace the metal screw in the bracket.
6. Complete the wiring as shown in the
appropriate diagram.
7. Read the checkout procedure.
8. Relay bracket must not come in contact
with metal.
1. Not approved for directly controlling motors of
safety related applications.
2. Always disconnect power before working on the
Current Sensing Relay or its connected load.
3. Follow all local electrical and safety codes,
the National Electrical Code (NEC), and OSHA
requirements.
HUMIDIFIER
MODEL
50
CURRENT
SENSING
RELAY
METAL BRACKET
COMMON LEAD
FURNACE
BLOWER
MOTOR
COMMON
24
VAC
120 VAC
TRANSFORMER
R C A B ODT CfW/G H
FURNACE
BLOWER
MOTOR
MODEL
50
HUMIDIFIER
AUTOMATIC CONTROL TERMINAL STRIP
24V
COMMON LEAD
METAL BRACKET
COMMON
CURRENT
SENSING
RELAY
JUMPER WIRES REQUIRED
FOR THE AUTOMATIC DIGITAL
HUMIDIFIER CONTROL ONLY
NOTE: SET THE WATER PANEL
CHANGE INDICATOR TO THE “OFF”
POSITION WHEN USING THE MODEL
50 CURRENT SENSING RELAY WITH
AUTOMATIC CONTROL.
90-1251 90-1249
90-908
LOAD
RELAY
24 or
120 VAC
COMMON
LEAD
4 Amp. min.
90-909
10005113_B AA Model 50-51 Install 1/11/08 12:30 PM Page 1