BAPI 900 Installation & Operation Manual

17614_ins_wireless_900_rcvr

Installation and Operating Instructions

Wireless 900 MHz Receiver

Building Automation Products, Inc., 750 North Royal Avenue, Gays Mills, WI  54631 USA

Tel:+1-608-735-4800 • Fax+1-608-735-4804 • E-mail:sales@bapihvac.com • Web:www.bapihvac.com

Specifications subject to change without notice.

rev. 04/21/15

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Overview and Identification

The BAPI 900 MHz unit receives a 

repeated or re-transmitted RF signal from one 

or more wireless temperature or humidity transmitters. The signal from the transmitter 

(418 MHz) is received by a 

BAPI Repeater and then re-transmitted at 900 MHz up to 

1,000 feet to the 900 MHz Receiver. 

The receiver then outputs the values to any Analog Output Module through an RS485 

four-wire bus.  The Analog Output Modules convert the signal to an analog voltage, 

current or resistance for the controller. The receiver can accommodate up to 127 

different Analog Output Modules. It is surface, snaptrack or DIN rail mountable with a 

79” extendable antenna for optimum recep-

tion.

Note: The 900 MHz Receiver will only 

receive a signal from a Repeater. It will not 

receive the signal from the transmitters, 

which transmit at 418 MHz.

Customer Provided Tools and Materials

#2 Philips Screwdriver, Drill, Wire

Analog Output Module Training 

The installation process requires that each transmitter is trained to 

its associated output module or modules so that they receive com-

munications from the correct transmitter.  Pushing buttons in a de-

fined sequence on the transmitter and output module will bind the 

two units together. The training process is easiest on a test bench 

so that the transmitter and receiver/output modules are within 

arm’s reach of each other.  Training can be done in the field but will 

require two people and a set of walkie talkies or cell phones. Be 

sure to place a unique identification mark on the transmitter and 

associated output module or modules after they have been trained 

so that they can be matched together at the job site.

If more than one variable is transmitted by the room transmitter 

(temperature, humidity and setpoint for instance), each variable 

requires a separate output module.  Perform the training sequence 

for each output module.  Any transmitted variable can be trained to 

more than one output module.

TEMPERATURE OR HUMIDITY VARIABLE TRAINING

1.   To train an output module to a Temperature or Humidity 

variable, select the Resistance, Voltage or Current Output Module calibrated to the 

temperature or humidity range you need and connect it to the wireless receiver. Note: 

Multiple output modules can be trained to the same transmitter variable if desired. 

2.   Apply power to the receiver which will supply power to the connected output modules. 

The power LED on the receiver will light and remain lit. 

(Current Output Modules 

must have loop power supplied to the module itself before they can be trained.)  

3.   Remove the cover of the room transmitter and remove the battery tabs or install the 

batteries, observing polarity as shown in Fig 2.  The small LED at the bottom right of 

the circuit board, next to the setpoint, will flash approximately once every 20 seconds, 

indicating a transmission. (The flash is very quick.)

Fig. 3: Output Module

Service Button

Battery polarity 

important or damage 

to the unit may occur

Training 

Button

Override 

Button

Transmit 

LED

Setpoint

Slider

Fig. 2: Room Transmitter with 

Optional Setpoint and 

Override. 

Continued on next page....

Fig. 1: Two views of the 900 

MHz Receiver.