RF Innovations RFI-148 User manual

RFI-148 250W VHF PAGING
TRANSMITTER
USER MANUAL

RFI-148 250W VHF Paging Transmitter
User Manual
DISCLAIMER
© 2013 RF Innovations Pty Ltd. All rights reserved.
RF Innovations reserves the right to make improvements on the product in this manual at any time without
notice.
No part of this manual may be produced, copied, translated, or transmitted in any form or by any means
without the written permission of RF Innovations.
Information provided in this manual is intended to be accurate and reliable. However, RF Innovations
assumes no responsibility for its use or infringements upon the rights of third parties that may result from its
use.
Reference No. MAN00165
Revision 1.6
January 2013
Firmware Version 0.6

Contents
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Contents
1. Introduction................................................................................................................................................................................... 5
2. Installation ..................................................................................................................................................................................... 6
2.1 General Considerations............................................................................................................................................................ 6
2.2 External Antennas .................................................................................................................................................................... 6
2.3 Product Installation.................................................................................................................................................................. 7
2.4 Safety and Compliance............................................................................................................................................................. 8
2.4.1 Human Exposure to Emissions......................................................................................................................................... 8
2.4.2 Modifications.................................................................................................................................................................... 8
3. Configuration................................................................................................................................................................................. 9
3.1 Overview................................................................................................................................................................................... 9
3.2 Cruise Control.......................................................................................................................................................................... 9
3.2.1 Installation ...................................................................................................................................................................... 10
3.2.2 Connecting to the Paging Transmitter ............................................................................................................................ 10
3.2.3 Device Navigation .......................................................................................................................................................... 11
3.2.4 Sensor Gauges ................................................................................................................................................................ 11
3.2.5 Firmware Update ............................................................................................................................................................ 13
3.3 SNMP...................................................................................................................................................................................... 13
3.4 Terminal Menu Interface........................................................................................................................................................ 13
3.5 Hayes AT Command Interface................................................................................................................................................ 13
3.6 Front Panel Interface ............................................................................................................................................................. 14
3.7 LIU Interface .......................................................................................................................................................................... 15
4. Operation ..................................................................................................................................................................................... 17
4.1 Serial Port Operation............................................................................................................................................................. 17
4.1.1 Overview......................................................................................................................................................................... 17
4.1.2 Configuration.................................................................................................................................................................. 17
4.1.3 Statistics.......................................................................................................................................................................... 17
4.2 Ethernet Operation................................................................................................................................................................. 17
4.2.1 Overview......................................................................................................................................................................... 17
4.2.2 IP Addressing.................................................................................................................................................................. 18
4.3 Transmitter Operation............................................................................................................................................................ 18
4.3.1 Transmit Power............................................................................................................................................................... 18
4.3.2 Channel Selection ........................................................................................................................................................... 18
4.3.3 Push-To-Talk (PTT) ....................................................................................................................................................... 18
4.3.4 External Reference.......................................................................................................................................................... 19
4.3.5 Absolute Delay Adjustment............................................................................................................................................ 19
4.3.6 Carrier Offset.................................................................................................................................................................. 19
4.3.7 RF Diagnostics................................................................................................................................................................ 19
4.4 Data........................................................................................................................................................................................ 19
4.5 Fan Control............................................................................................................................................................................ 20
4.5.1 Current Fan Speed .......................................................................................................................................................... 20
4.5.2 Control Types ................................................................................................................................................................. 20
4.5.3 Fan Override................................................................................................................................................................... 20
4.5.4 Self-Test.......................................................................................................................................................................... 20
5. Diagnostics ................................................................................................................................................................................... 21
5.1 Status Monitoring................................................................................................................................................................... 21

Contents
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5.1.1 Conditional Cut-off Checking......................................................................................................................................... 21
5.1.2 Minimum and Maximum Sensor History ....................................................................................................................... 22
5.2 Faults...................................................................................................................................................................................... 22
5.2.1 Fault Actions................................................................................................................................................................... 22
5.2.2 Fleeting Faults ................................................................................................................................................................ 23
5.2.3 Combined Fault .............................................................................................................................................................. 23
5.2.4 Hardware Alarm Outputs................................................................................................................................................ 23
5.3 Remote Firmware Update and Recovery................................................................................................................................ 23
5.3.1 Update............................................................................................................................................................................. 23
5.3.2 Recovery......................................................................................................................................................................... 24
5.4 Time........................................................................................................................................................................................ 24
5.4.1 Real Time Clock............................................................................................................................................................. 24
5.4.2 SNTP Client.................................................................................................................................................................... 24
Appendix A Technical Specifications ............................................................................................................................................ 25
A.1 Type Approvals ...................................................................................................................................................................... 25
A.2 RFI-148 250 Specifications.................................................................................................................................................... 25
A.3 Serial Connectors................................................................................................................................................................... 26
A.3.1 Main Serial Port (Rear) ................................................................................................................................................. 26
A.3.2 Auxiliary Serial Port (Front).......................................................................................................................................... 27
A.4 LIU Interface.......................................................................................................................................................................... 27
Appendix B Controller Configurations......................................................................................................................................... 29
B.1 Motorola NIU Controller / FLEX Mode ................................................................................................................................ 29
B.2 Glenayre C2000 Controller / FLEX Mode............................................................................................................................. 29
B.3 Glenayre C2000 Controller / POCSAG Mode....................................................................................................................... 29
B.4 Zetron Model 66 Transmitter Controller / POCSAG Mode................................................................................................... 30
Appendix C Management Reference............................................................................................................................................. 31
C.1 Serial Port Diagnostics.......................................................................................................................................................... 31
C.2 SNMP Diagnostic Parameters............................................................................................................................................... 31
Appendix D Hayes References ....................................................................................................................................................... 33
D.1 General Commands............................................................................................................................................................... 33
D.2 I-Registers.............................................................................................................................................................................. 33
Appendix E Sensor and Fault List Reference............................................................................................................................... 36
Appendix F Factory Defaults ......................................................................................................................................................... 40
Appendix G Glossary...................................................................................................................................................................... 42

Introduction
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1. Introduction
The RFI-148 250 is a high power output paging transmitter operating in the VHF band.
VHF band operation (138 MHz –174 MHz)
with 2 MHz switching bandwidth.
250 W (54 dBm) maximum transmit power
Compatible with:
POCSAG 512, 1200, 2400 bps (2-level
FSK).
FLEX 1600 (2-level FSK), 3200 (2- or 4-
level FSK), 6400 bps (4-level FSK).
Windows GUI for configuration and
diagnostics over serial or network (Cruise
Control).
SNMP diagnostics.
DSP precision modulation.
Integrated isolator.
RF diagnostics port for in-rack receiver.
Remote firmware update capability.
Software selectable frequency offset.
Adjustable absolute delay correction.
Hardware alarm outputs.
Front panel indicators for power output and
diagnostics.
High frequency stability and external
reference option.

Installation
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2. Installation
2.1 General Considerations
There are a number of rules to observe when installing a paging transmitter.
Antenna selection is vital to a good RF link. Different antennas are required depending on the application.
Please contact your antenna manufacturer or RF Innovations for correct antenna selection.
Antenna placement has a significant impact on RF link performance. In general, higher antenna placement
results in a better communication link. A vantage point should be chosen to clear the propagation ellipsoid.
An unobstructed, line-of-sight link will always perform better than a cluttered or obstructed link.
Obstructions, such as walls and poles, will distort the antenna radiation pattern and VSWR, resulting in less
efficient transmission and reception.
Antennas in close proximity are potential sources of mutual interference. A transmitter can cause overload of
a nearby receiver, if due precautions are not taken in antenna location. Moreover, transmitters in close
proximity may cause intermodulation. Slight adjustments in antenna placement may help solving
interference problems.
All items of radio equipment, such as antennas, are sources of RF radiation. They should thus be placed
away from electrical equipment, such as computers, telephones or answering machines.
Serial cable runs between radio modem and attached terminal equipment (eg RTU or PC) should be kept as
small as possible. A maximum cable capacitance of 2,400 pF is recommended for transfer rates up to 19.2
kbit/s. If a non-shielded, 30 pF / foot cable is used, the maximum length should be limited to 80 feet
(approximately 24m). For higher interface speeds, the length of the serial cable should be shortened.
Long serial cables should also be avoided in areas with frequent lightning activity or static electricity build-
up. Nearby lightning strikes or high levels of static electricity may lead to interface failure.
RF Innovations supplies a range of external data interface converters for applications requiring long cable
runs.
2.2 External Antennas
Long antenna feed lines cause RF loss, both in transmission and reception levels, and degrade link
performance. When long cable runs are required use a suitable low-loss cable.
As an example, RG58 (tinned-copper braid) will exhibit a loss of 7.1 dB / 30 m at 148 MHz –174 MHz,
whereas RG58 CellFoil will exhibit 3 dB less (4.2 dB / 30 m).
Antennas should not be located within close reach of people, due to radiation hazard. Exposure guidelines
should be followed at all times.
Use extreme caution when installing antennas and follow all instructions provided. Because external
antennas are subject lightning strikes, RF Innovations recommends protecting all antennas against lighting
strike by using lightning surge arrestors.

Installation
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2.3 Product Installation
The back panel of the paging transmitter is shown below in Figure 1.
1. System
Ground
2. RF Output
3. External
Frequency
4. Ethernet
5. DC Input
24 V Nominal
6. DC SW
7. RF Diag
8. LIU
Interface
9. RS232
Figure 1: Paging Transmitter Back Panel
1. System Ground: External connection for system ground.
2. RF Output: Modulated RF output from the paging transmitter. N-type female connector.
3. External Frequency: External reference input for accurate channel synthesis. BNC female
connector.
4. Ethernet: Ethernet connection for configuration and diagnostics over UDP. RJ45 connector.
5. DC Input 24 V Nominal: 20-31.2 V DC Input voltage. Terminal block connector.
6. RF Diag: Sniffer port for diagnostics. BNC female connector.
7. DC SW: Power switch.
8. LIU Interface: Combined alarm and encoder interface. DC-37 female connector.
9. RS-232: Main serial port. DE-9 female connector.

Installation
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2.4 Safety and Compliance
2.4.1 Human Exposure to Emissions
To limit human exposure, the following guidelines need to be observed:
1. Take reasonable precautions in any installation to maintain a clearance from the antenna of no less
than 4 m (four metres) to the general public and 2 m (two metres) to service and maintenance
personnel.
2. Do not apply power to the device unless the clearance described in 1 above has been allowed.
The guidelines above apply when transmitting at maximum power, with an antenna gain of up to 13 dB.
For further information on human RF exposure, contact your local health department. For example, Health
Canada’s Safety Code 6 provides a comprehensive set of guidelines.
2.4.2 Modifications
CAUTION: Changes or modifications not expressly approved by RF Innovations may void the user’s
authority to operate the equipment legally, as well as any warranty provided.

Configuration
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3. Configuration
3.1 Overview
The RFI-148 250 provides six interfaces that allow the transmitter to be configured and diagnostic
information to be monitored:
Cruise Control management interface: All configuration and diagnostics parameters can be
accessed using the Windows-based Cruise Control Graphical User Interface (GUI).
SNMP interface: Support for diagnostics using SNMP.
Terminal menu interface: A navigable menu system is available that has all the configuration and
diagnostics that Cruise Control provides.
AT command interface: The AT command interface provides a subset of the configuration and
diagnostic information available over Cruise Control with ASCII Hayes attention commands.
Front panel interface: The front panel consists of five status LEDs and a transmit power gauge.
LIU interface: The combined LIU interface has digital inputs and alarm outputs for limited
configuration and diagnostic output.
3.2 Cruise Control
The following sections briefly outline how to use Cruise Control with the paging transmitter. For more
information see the Cruise Control User Manual. Figure 2 below is a typical screenshot of the Cruise Control
interface running on Windows 7.

Configuration
RFI-148 250W VHF Paging Transmitter User Manual Page 10 of 43
Figure 2: Cruise Control Interface
3.2.1 Installation
The requirements for using the Cruise Control application are:
Pentium III+ Processor.
Windows XP (x86) or Windows 7 (x86 and x64).
At least 1 available serial port or a network connection to the device.
3.2.2 Connecting to the Paging Transmitter
SERIAL
To connect to a device with RS-232, attach the paging transmitter to the PC running Cruise Control via a
serial port. Configure the Cruise Control communication settings using Device -> Configure

Configuration
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Communications, ensure that Serial is selected from the dropdown box and enter in the serial settings
(19200 8N1 by default).
Use the Device -> Connect to Local Device menu item to connect to the local device.
ETHERNET
To connect to a device over a network, the device IP address must be known. Configure the Cruise Control
communication settings using Device -> Configure Communications, ensure that UDP is selected
from the dropdown box and enter the device IP address. For the UDP port, enter 64250, 64251 or 64252.
The paging transmitter listens on UDP ports 64250, 64251 and 64252 for data and will not allow more than
one simultaneous session per port. If the paging transmitter does not respond to Cruise Control on a UDP
port, try another port as a connection could already be active on that port.
Use the Device -> Connect to Local Device menu item to connect to the device.
3.2.3 Device Navigation
Once all the settings have been downloaded from the device, the available configuration groups are
displayed in a tree on the left. The items that can be configured in each group are displayed in tables on the
right.
The names of editable items are displayed in black. Read only items have their names in grey.
3.2.4 Sensor Gauges
Cruise Control can provide real-time operational information for paging transmitters using the Sensor
Gauges plugin. An example of diagnostic information provided by the Sensor Gauges plugin is shown below
in Figure 3.

Configuration
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Figure 3: Cruise Control Sensor Gauges Plugin
To view Sensor Gauges for a paging transmitter, first connect to the paging transmitter using Cruise Control.
Then use the Tools -> Plugins -> Sensor Gauges menu item to open the Sensor Gauges plugin.
The Sensor Gauges will automatically update, with the needles showing the current value of the gauge
parameter. The green region indicates the expected normal operating value for the parameter. The upper and
lower cut-off values for the sensor (see section 5.1) determine the range of the green region. There is a red
indicator below each gauge which turns on when the parameter exceeds the upper or lower cut-off value.
The Groups option box on the left shows the different groups of gauges available, grouped by the unit of
measurement of the sensor. There are also two additional groups, overview and all. The overview group
provides a subset of the most informative gauges for quick diagnostic troubleshooting. The all group shows
all of the gauges.

Configuration
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3.2.5 Firmware Update
Cruise Control supports the updating of device firmware from Motorola S-Record image files (*.mot).
Cruise Control will only allow firmware images that are compatible with the paging transmitter to be
uploaded.
To upload a firmware image use the Device -> Load Firmware menu item. A windows explorer dialog
will open, navigate to where the firmware image is on the computer, select the image and click upload. The
progress bar at the bottom right will show the progress of the firmware update.
Once the upload has finished the paging transmitter will reset to apply the update. While updating the paging
transmitter cannot key up or respond to queries. Cruise Control will automatically reconnect once the update
is complete.
For information on this feature as related to the paging transmitter firmware, which includes the firmware
recovery mechanism, see section 5.3.
3.3 SNMP
The paging transmitter includes a built-in SNMP agent. Not all configuration and diagnostic parameters may
be queried via SNMP. See Appendix C.2 for a list of values which may be queried via SNMP.
SNMP versions 1 and 2c are supported. The community string ‘public’ should be used when issuing SNMP
requests. The agent responds on UDP port 161 is compatible with standard SNMP managers and other
SNMP client applications.
An SMI MIB file defining OIDs for this product is available.
3.4 Terminal Menu Interface
The terminal menu provides access to all configuration parameters in the radio.
To access the terminal menu execute the AT? command at the Hayes AT command interface. See section 3.5
on page 13 for information on executing AT commands. The terminal menu will not be started if it is open
on another port, instead the BUSY response is returned.
The terminal menu is available over serial, UDP (ports 64250, 64251 and 64252) and TCP (port 23).
3.5 Hayes AT Command Interface
The paging transmitter supports Hayes ATtention commands. These are used to query and change device
configuration and probe performance parameters. AT commands are available via serial port, and via TCP
port 23 on the Ethernet interface.
The format for the query and configuration AT command is:
ATxxx<[I1, I2, … In]><=value><TERM>

Configuration
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Where:
AT is the attention code. All AT commands must be prefixed with AT. This is case insensitive, so
At, aT, or at can also be used.
xxx is the actual command. The list of valid AT commands is given in Appendix D on page 33.
<[I1, I2, … In]> is an optional section that allows the specification of an index. Indexes are
used to access one of an array of similar items. For example, the Crescendo radio has two serial
ports which can both have different configurations. The command ATS52[0]=1004 set the point-
to-point destination on the main port, while the command ATS52[1]=1004 will set the point-to-
point destination on the auxiliary port.
<=value> is an optional section that is used to set the value of a configuration parameter. If this
section is omitted, then the value of the configuration parameter will be displayed.
<TERM> is the terminator for the AT command. A terminator can consist of a carriage return
(ASCII value 13Decimal) or a carriage return followed by a line feed (ASCII value 10Decimal).
For each AT command that is issued a response is generated. The list of responses to AT commands is
shown in Table 1.
Response
Code
Response
Number
Description
OK
0
Returned whenever a command is entered that is executed correctly.
ERROR
4
Returned whenever a command is invalid or could not be executed.
BUSY
7
Returned when an attempt is made to enable the menu via AT? but the menu
system is already enabled on the other serial port.
Table 1: AT command response codes
3.6 Front Panel Interface
The front panel interface consists of 6 status LEDs and a transmit power gauge. The panel is illustrated in
Figure 4 and the function of each LED is described in Table 2.
LED
Colour
Description
Transmit On
Green
Turns on when the transmitter is on.
Fault
Red
Turns on when any fault is active.
Low Power
Red
Turns on when the sensed transmit power is lower than the
lower cut-off value as specified in the sensor parameters.
High VSWR
Red
Turns on when the isolator VSWR is higher than the higher
cut-off value as specified in the sensor parameters.
Serial/Ethernet
Green
Flashes when serial or Ethernet data is transmitted or
received.
Power
Green
Turns on/off at 1 Hz while power is supplied.
Power Gauge
Green/Red
A bar graph displaying current transmit power.
Table 2: Front panel LED descriptions

Configuration
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TRANSMIT ON
FAULT
LOW POWER
HIGH VSWR
SERIAL/ETHERNET
POWER
25
250
125
TX POWER (W)
Figure 4: Front panel display
3.7 LIU Interface
The LIU interface is a DC-37 female connector at the rear of the paging transmitter. The LIU interface has
the following connections:
Nine digital inputs:
Frequency Select 1
Frequency Select 2
Frequency Select 3
Frequency Select 4
Protocol Select
Hardware PTT
Tx Data L-bit
Tx Data H-bit
Transmit Clock
Fourteen alarm outputs:
Power Supply Alarm
Reference Out-of-Lock Alarm
Reference Switchover Alarm
High Output Power Alarm
Low Output Power Alarm
High VSWR Alarm
High Temperature Alarm
Fan Failure Alarm
Exciter Out-of-Lock Alarm
Combined Alarm

Configuration
RFI-148 250W VHF Paging Transmitter User Manual Page 16 of 43
Spare Alarm 1
Spare Alarm 2
Spare Alarm 3
Spare Alarm 4
Use of the hardware PTT, protocol select and frequency select inputs are all optional and may be disabled in
software. The use of the transmit clock is optional for 2-level protocols, but required for 4-level protocols.
The pin-out for the LIU Interface can be found in Appendix A.4

Operation
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4. Operation
4.1 Serial Port Operation
4.1.1 Overview
The RFI-148 250 has two DCE RS-232 serial ports. The front serial port has a female DE9 connector (DCE)
and the rear serial port has a male DE9 connector (DTE). The serial port pin outs can be found in Appendix
A.3 on page 26.
The main port (at the back of the transmitter) supports:
TX, RX, and GND.
RTS and DTR inputs.
CTS and DCD outputs.
The auxiliary (at the front of the transmitter) port supports:
TX, RX, and GND.
4.1.2 Configuration
Both main and auxiliary serial ports support the following configuration options:
Baud rate: 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600 or 115200.
Data bits: 7 or 8
Parity: None, odd, or even
Stop bits: 1 or 2
4.1.3 Statistics
Statistics are maintained for both serial ports. These statistics are listed in Table 12 in Appendix C.1. All
statistics are reset if power is removed.
These statistics may be useful in troubleshooting. For example, Rx framing errors may indicate that the
serial port configuration does not match the serial port configuration of the DTE.
4.2 Ethernet Operation
4.2.1 Overview
The paging transmitter has one 10BASE-T/100BASE-TX Ethernet port. Auto-negotiation of link speed is
supported, including duplex mode. There is also a software override for forcing the parameters of the link.

Operation
RFI-148 250W VHF Paging Transmitter User Manual Page 18 of 43
4.2.2 IP Addressing
The paging transmitter supports IPv4. The IP address may be configured with a single static address. A
subnet mask and default gateway may be configured to allow communication across sub-networks.
4.3 Transmitter Operation
4.3.1 Transmit Power
The RFI-148 250 supports transmit power from 20 to 250 Watts in 1 Watt increments.
4.3.2 Channel Selection
The transmitter supports four channel rasters: 5 kHz; 6.25 kHz; 10 kHz; and 12.5 kHz, and has up to sixteen
configurable channels. The transmit frequency of each channel can be configured using the Cruise Control
GUI. The current operating channel can be selected using the Cruise Control GUI, Hayes AT commands, a
terminal interface or the LIU Interface.
4.3.3 Push-To-Talk (PTT)
There are three methods available to turn the transmitter on:
Software PTT: Software PTT is available using Hayes AT commands, through the Cruise Control
GUI, or through the terminal menu interface.
Hardware PTT: Hardware PTT is available through the LIU connector. Hardware PTT can be
configured to be active high or active low.
Auto PTT: Auto PTT is performed by detecting a change in the data bits on the LIU and turning on
the transmitter.
PTT TURN OFF DELAY
The unit has the option to leave the transmitter on for a set duration after receiving a PTT off signal. This
delay is driven by software and typically accurate to 100 ms.
TRANSMIT TIMEOUT
The unit can automatically raise a fault if the transmitter has been left on for too long. By default a transmit
timeout fault is raised if the transmitter is on for greater than 600 seconds (10 minutes). The default action
configured for the transmit timeout fault is to turn off the transmitter (see section 5.2). The ‘Enable transmit
timeout’ option must be set for this to occur. By default, this option is disabled.
PTT SYSTEM OVERRIDE
Transmitter PTT can be completely disabled using the PTT system override setting. By default it is set to
Enable Transmit.

Operation
RFI-148 250W VHF Paging Transmitter User Manual Page 19 of 43
4.3.4 External Reference
The transmitter supports an external reference for channel frequency generation. To use the external
reference, a 10 MHz sine or square wave -10 dBm to 0 dBm signal must be applied to the “External
Frequency” input BNC connector on the back panel. The paging transmitter will attempt to use an external
reference by default.
AUTOMATIC REFERENCE SWITCHOVER
If the external reference is selected as the default reference, the transmitter will failover to the internal
reference in the event of the external reference failing.
The external reference is considered to have failed when there is no signal transition on the external
reference for at least two consecutive falling edges of the internal reference.
NOTE: If the paging transmitter is transmitting when reference switchover occurs, there may be data loss.
4.3.5 Absolute Delay Adjustment
The paging transmitter can insert a small artificial delay on data presented on the LIU interface before it is
passed to the digital synthesiser. The delay adjustment can be set from 0 to 40 ms in 5 µs steps. The
additional net delay is accurate to 3 µs.
4.3.6 Carrier Offset
A carrier offset from the channel frequency can be specified from -5000 to +5000 Hz in increments of 1 Hz.
4.3.7 RF Diagnostics
The paging transmitter provides an RF diagnostics port output on the back panel. The RF diagnostics port
can be configured for two modes:
Transmission: The sniffer port will output a signal identical to that of RF out, attenuated by
approximately 105 dB. This is the normal mode of operation.
Listening: Attenuation from the antenna port to the sniffer port is reduced to less than 15 dB. This is
a special mode of operation used for network testing. NOTE: While the sniffer port is configured for
listening, transmission is disabled.
4.4 Data
The RFI-148 250 supports the following modulation formats:
POCSAG: Baud rates of 512, 1200 and 2400 bps (2-level FSK) are supported.
FLEX: Baud rates of 1600 (2-level FSK), 3200 (2-level or 4-level FSK) and 6400 bps (4-level FSK)
are supported.

Operation
RFI-148 250W VHF Paging Transmitter User Manual Page 20 of 43
2-level FSK protocol data may optionally be clocked into the paging transmitter using the external data
clock or may run asynchronously. 4-level FSK protocols must use the external data clock.
Once the desired paging protocol, deviation and carrier offset settings have been selected, the Save
Protocols routine must be executed to apply the selected settings.
4.5 Fan Control
The transmitter has two fans for cooling; the front fan is an intake and the rear fan is the exhaust.
4.5.1 Current Fan Speed
The current fan speed displays the target fan speed by the fan controller as a percentage of total possible fan
speed. This value is set by the paging transmitter and depends on the fan control type, current temperature,
whether fan override is enabled or a fan test is in progress.
4.5.2 Control Types
The fans have two control types:
On/off: The fans will turn on and off at a specified temperature. The fans turn on at the speed
specified by the fan speed setting parameter.
Linear scaling: The fans will increase in speed as the transmitter heats up. The fan turn on and fan
turn off temperatures determine the how quickly the fans respond to increases in temperature. Once
the temperature exceeds the fan turn on temperature, the fans will then be set to full speed.
The fan control types act from a configurable temperature sensor. By default the fan controller will use the
highest temperature of all the temperature sensors.
4.5.3 Fan Override
There is a fan override feature available to force the fans to turn on at full speed. When fan override is
enabled the fans will ramp up to full speed and ignore the configured control type. Otherwise, the fans turn
off and on as specified by the control type.
4.5.4 Self-Test
The fan controller has a self-test feature which causes the fans to run at full speed for a minute so fan
operation can be verified. The self-test feature runs once every 24 hours by default.