Macurco BRS-485 User manual

IMPORTANT: Keep these user instructions for reference.
Macurco™ BRS-485
Multi-protocol RS-485 Adapter
User Instructions

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 2 |Page
Table of Contents
1General Safety Information.................................................................................................................... 4
1.1 List of warnings............................................................................................................................... 4
2Use Instructions and Limitations ............................................................................................................ 5
2.1 Use For ........................................................................................................................................... 5
2.2 Do NOT use for ............................................................................................................................... 5
2.3 Features.......................................................................................................................................... 6
2.4 Specifications.................................................................................................................................. 7
3Installation Instructions.......................................................................................................................... 8
3.1 Location .......................................................................................................................................... 8
3.2 Installation...................................................................................................................................... 8
3.3 Connection ................................................................................................................................... 10
3.4 Wiring........................................................................................................................................... 11
3.4.1 Signal Wire...................................................................................................................... 11
3.4.2 Topology ......................................................................................................................... 11
3.4.3 Length............................................................................................................................. 12
3.4.4 Grounding....................................................................................................................... 12
3.4.5 Power Wire..................................................................................................................... 13
4Configuration ....................................................................................................................................... 14
4.1 Macurco NPU Software ................................................................................................................. 15
4.2 Addressing and Communication Settings ...................................................................................... 16
4.3 Firmware and Configuration Update ............................................................................................. 18
5Operations ........................................................................................................................................... 20
5.1 Power up ...................................................................................................................................... 20
5.2 4-20mA Loop ................................................................................................................................ 20
5.3 Normal Operation ......................................................................................................................... 20
6Troubleshooting................................................................................................................................... 21
6.1 On-Board Diagnostics.................................................................................................................... 21
6.1.1 Unknown Sensor Code .................................................................................................... 21
6.1.2 Error Codes ..................................................................................................................... 21
6.2 Status LED States .......................................................................................................................... 22

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 3 |Page
7Maintenance........................................................................................................................................ 23
7.1 Cleaning........................................................................................................................................ 23
8Testing ................................................................................................................................................. 24
8.1 Operation Test .............................................................................................................................. 24
8.2 Manual Operation Test ................................................................................................................. 25
9Appendix A........................................................................................................................................... 26
10 Appendix B – Table of Figures .............................................................................................................. 30
11 Macurco Gas Detection Product Limited Warranty .............................................................................. 31
Technical Support Contact Information ....................................................................................................... 32
General Contact Information ....................................................................................................................... 32

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 4 |Page
1General Safety Information
The Macurco BRS-485 Adapter is an accessory used to convert the 4-20mA analog signal from Macurco 6-Series
type detectors to a digital signal for use with multipoint addressable systems. The Macurco BRS-485 simply
connects to the back of the detector and a single screw fastens it in place. The BRS-485 accepts the 4-20mA
output and is powered from the same connection as the detector. The BRS-485 can interface with Building
Automation Systems, Control Panels or other Control Devices that accept Modbus, BACnet, Metasys and
Siemens communication protocol.
1.1 List of warnings
WARNING
Each person using this equipment must read and understand the information in this user manual before
use. Use of this equipment by untrained or unqualified persons or use that is not in accordance with this
user manual, may adversely affect product performance.
This equipment may not function effectively below 0°F or above 125°F (-18°C or above 52°C). Using the
detector outside of this temperature range may adversely affect product performance.
Do not disassemble unit or attempt to repair or modify any component of this instrument. This instrument
contains no user serviceable parts, and substitution of components may impair product performance and
void product warranty.

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 5 |Page
2Use Instructions and Limitations
WARNING
Each person using this equipment must read and understand the information in this user manual before
use. Use of this equipment by untrained or unqualified persons or use that is not in accordance with this
user manual, may adversely affect product performance.
2.1 Use For
The Macurco BRS-485 Adapter converts the Macurco 6-Series 4-20mA analog output to a digital output for use
with addressable network systems. The Macurco 6-Series is a family of fully programmable, low voltage, dual
relay gas detectors, controllers and transducers for BAS, HVAC and Fire & Security applications. The 6-Series
detectors are used to measure the concentration of various gases and provide feedback and automatic control
to help ensure a safe environment: Carbon Monoxide, Methane, Propane, Hydrogen, Nitrogen Dioxide and
other gases.
2.2 Do NOT use for
The BRS-485 is not intended for use in hazardous locations or industrial applications such as refineries, chemical
plants, etc. Do not mount the BRS-485 where the normal ambient temperature is below 0°F or exceeds 125°F (-
18°C or above 52°C). The BRS-485 mounts to a Macurco 6-Series detector installed on a 4” x 4” electrical box
electrical box supplied by the contractor.

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 6 |Page
2.3 Features
•The Macurco BRS-485 interfaces the detector power and 4-20mA output lines with a mounted connector
•The BRS-485 monitors sensor type, gas level and trouble status communications from any of the
Macurco 6-Series detectors
•Supports Modbus, BACnet, Metasys and Siemens communication protocol.
•Communication is on a serial line with a “Two-Wire” electrical interface in accordance with EIA/TIA-485
standard using RTU Transmission Mode
•Commercial type enclosure to protect and support the electronics
•Tricolor LED indicates power, test and communication status
•Mounts behind the detector inside of a standard 4” x 4” electrical box
•Held in place on the back of the 6-Series detector with a single screw
•USB connection to configure address and communication protocol and settings.
•RS-485 termination uses 3 pin connectors with jumper to select termination: The user selects no
termination or 120 Ohm termination.
•Communications connections include signal (A and B), Common and shield terminals
•Intended for use in non-hazardous areas such as parking garages, warehouses, or other commercial
facilities

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 7 |Page
2.4 Specifications
•Power & Current (without detector): 1.5W (max) from 12 to 24 VAC or VDC.
•Shipping Weight: 0.25 lb (0.11 kg)
•Size: 3 1/2 x 2 x 1 3/4 in. (8.9 X 5.1 X 4.4 cm)
•Operating Environment: 14°F to 122° F (-10°C to +50°C), 20 to 90% RH non-condensing
•Connections: plugs/terminals
•Color: Blue
•Mounting screw and screwdriver included
•BRS-485 operates as Modbus RTU Slave, BACnet MSTP Server, Metasys N2 Slave or Siemens FLN Slave
•Baud Rate:
Modbus: 2400, 4800, 9600, 19200 (default), 38400, 57600, 115200 bps
BACnet: 9600, 19200, 38400 (default), 57600, 76800, 115200 bps
Metasys N2 Slave: 9600
Siemens FLN Slave: 2400, 4800, 9600, 19200 (default), 38400, 57600, 115200 bps
•Parity:
Modbus: Odd, Even (default) and None
BACnet: No Parity
Metasys: No Parity
Siemens: No Parity

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 8 |Page
3Installation Instructions
The following instructions are intended to serve as a guideline for the use of the Macurco BRS-485 Adapter. It is
not to be considered all-inclusive, nor is it intended to replace the policy and procedures for each facility. If you
have any doubts about the applicability of the equipment to your situation, call Technical Support at 844-325-
3050.
WARNING
This equipment may not function effectively below 0°F or above 125°F (-18°C or above 52°C). Using the
detector outside of this temperature range may adversely affect product performance.
3.1 Location
Refer to the user instructions of the specific Macurco 6-Series gas detector to which the BRS-485 will be
connected.
3.2 Installation
The Macurco BRS-485 Adapter converts the Macurco 6-Series 4-20mA analog output to a digital output for use
with addressable network systems. The Macurco 6-Series is a family of fully programmable, low voltage, dual
relay gas detectors, controllers and transducers for BAS, HVAC and Fire & Security applications. The 6-Series
detectors are used to measure the concentration of various gas and provide feedback and automatic control to
help ensure a safe environment: Carbon Monoxide, Methane, Propane, Hydrogen, Nitrogen Dioxide and other
gases.
1. Remove the 4-20mA/Power connector from the Macurco 6-Series gas detector.
2. Plug the BRS-485 adapter into the empty 4-pin socket.
3. Install the provided BRS-485 screw.
4. See the wiring diagram for wire connection.

Macurco MRS-485 Modbus RS-485 Adapter
REV – 1.0 [34-2900-0019-7] 9 |Page
Figure 3-1 BRS-485 Installation Expanded
5. The 6-Series detector mounts on a 4”x 4” electrical box supplied by the contractor.
6. Connect the detector to the control cables with terminal plugs. When making connections, make sure
the power is off.
7. There are two terminals for the dry alarm relay contacts, again with no polarity preference. The alarm
relay can switch up to 0.5 A 120 V, or 60 VA. The alarm relay is activated if gas reaches or exceeds the
alarm settings. See Operation of the detector User Instructions for details on relay settings.
8. The alarm relay can be configured to normally open (default) (N.O.) or normally closed (N.C.) and will
activate if the gas concentration exceeds alarm set point. It will deactivate once the gas concentration
drops below the alarm set point. Note that the “disable” setting will cause the alarm relay not to engage
at all.
9. The dry contact, SPDT fan relay has three terminals: The Common (COM), normally open (N.O.) and the
normally closed (N.C.) contact. The fan relay can switch up to 5.0 A up to 240 VAC. See Operation section
of the detector User Instructions for details on relay settings.