Johnson Controls R45 Series Service manual

FANs 121, 125
Relays and Contactors Section R
Technical Bulletin R45
Issue Date 0882
© 1982 Johnson Controls, Inc. 1
Part No. 24-4229-5, Rev. —
Code No. LIT-121565
R45 Series
Electronic Interface
Application
These electronic interfaces are
for installations where a mixture
of Johnson Controls
CYBERTRONIC®and R41 or
R48 economizer equipment is
required.
Features
•provides flexibility
•adds new capability
•easy to wire and install
•simple to adjust
General Description
The R45AA and R45AB interfaces
allow the economizer control
signal to control one or more
CYBERTRONIC controlled
devices.
They convert the R41 or R48
economizer's +2 to +18 V.D.C.
signal into the 0 to -16 V.D.C.
signal needed to operate the
CYBERTRONIC products.
The R45GA and R45GB
interfaces allow the
CYBERTRONIC control signal to
control one or more economizer
devices. They convert the
CYBERTRONIC 0 to -16 V.D.C.
signal into the +2 to +18 V.D.C.
signal needed to operate
economizer products.
The electronic interfaces also
match the impedances to the
two product lines.
Installation
These interfaces have two holes
for mounting in a standard 2 in. x
4 in. switch box. Prior to final
mounting, the calibration
procedure should be performed.
Fig. 1 -- R45 Electronic Interface.
They mount with transformer,
adjustment potentiometer, and
wire leads inside the switch box.
An insulating shield covers the
board to prevent shorting when
the cover is screwed down on
the box. (See Fig. 2.)
Wiring
!
CAUTION: Disconnect
power supply before wiring
and mounting connections
are made to prevent
electrical shock and
possible damage to the
equipment.
All wiring must be in accordance
with local regulations and
Electrical Codes.
The interfaces are supplied with
color coded wire leads. See
Figs. 3 and 4 for wiring
diagrams.
Specifications

2 R45 Technical Bulletin
All connections should be made
using No. 18 AWG wire. The
connections should be made
within the switch box with wire
nuts or solder and tape.
Recheck connections before
applying power to the interface.
Calibration Procedure
The R45A( ) Economizer to
CYBERTRONIC Interface
1. Connect the
CYBERTRONIC load or a
1000 ohm resistor across
the Red (+) and Blue (-)
output leads.
2. Connect appropriate supply
voltage.
3. Apply 2 V.D.C. to the
White/Red (+) and
White/Blue (-) input leads.
4. Adjust the zero
potentiometer until
0.01 V.D.C. is read across
the output leads. Slowly
decrease the zero
potentiometer until
0.05 V.D.C. is just read.
5. Increase the input voltage to
18 V.D.C.
6. Adjust the span
potentiometer for an output
reading of -16 V.D.C.
7. Repeat Steps 3 through 6 to
achieve precise calibration.
The R45G( ) CYBERTRONIC to
Economizer Interface
1. Connect the economizer
load or a 10 k ohm resistor
across the Red (+) and Blue
(-) output leads.
2. Connect appropriate supply
voltage.
3. Apply zero V.D.C. to the
White/Red (+) and
White/Blue (-) input leads.
4. Adjust the zero
potentiometer until the
+2 V.D.C. is read across the
output leads.
5. Apply -16 V.D.C. to the
input.
6. Adjust the span
potentiometer for an output
reading of +18 V.D.C.
7. Repeat Steps 3 through 6 to
achieve precise calibration.
Checkout Procedure
Before leaving the installation,
several complete operating
cycles of the system should be
observed to see that all
components are functioning
properly.
Repairs and Replacement
Field repairs must not be made.
For a replacement interface,
contact the nearest Johnson
Controls Commercial Systems
wholesaler.
Ordering Information
To order, specify Complete
Product Number.
Performance specifications
appearing herein are nominal
and are subject to accepted
manufacturing tolerances and
application variables.
Controls Group
507 E. Michigan Street
P.O. Box 423 Printed in U.S.A.
Milwaukee, WI 53202