Macurco Modbus RS-485 User manual

Macurco ™ Modbus ® RS-485 Adapter MRS-485
User Instructions
IMPORTANT: Keep these User Instructions for reference

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TABLE OF CONTENTS
GENERAL SAFETY INFORMATION 3
Intended Use 3
List of Warnings and Cautions 3
USE INSTRUCTIONS AND LIMITATIONS 3
UseFor 3
Do Not Use For 3
General Description 4
Features 4
Specifications 4
INSTALLATION AND OPERATING INSTRUCTIONS 5
Location 5
Installation 5
Rear exploded view 5
Front exploded view 6
Connection 6
Wiring 7
Signal wire 7
Topology 7
Typical connection diagram 7
Length 8
Grounding 8
Power 8
DIP Switches and Addressing 8
DIP Switch Figure 8
Settings 9
Programming 9
Line Termination 10
MRS-485 Detail 10
Dip Switch setting Table 11
Power-Up 12
4-20mA Test Points 12
Operation 12
Normal Operation 12
On Board Diagnostics 13
Error Codes 13
DIP Switch Setting Codes 13
Testing 14
General 14
Operation Test 14
Manual Operation Test 14
MAINTENANCE 15
Cleaning 15
MACURCO GAS DETECTION PRODUCTS WARRANTY 16

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GENERAL SAFETY INFORMATION
Intended Use
The Macurco MRS-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 multipointaddressable systems. The Macurco MRS-485 simply plugs into the back of the detectorand a
single screw fastens it in place. The MRS-485 accepts the 4-20mA output and is powered from the same connection as the
detector. The MRS-485 has the ability to interface with Building Automation Systems, Control Panels or other Control Devices that
accept Modbus communications.
List of Warnings and Cautions within these User Instructions
Each person using this equipment must read and understand the information in these User Instructions before use. Use of this
equipment by untrained or unqualified persons, or use that is not in accordance with these User Instructions, may adversely
affect product performance and result in sickness ordeath.
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 temperaturerange may adversely affect product performance and resultin sicknessor death.
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 result in sickness ordeath.
USE INSTRUCTIONS AND LIMITATIONS
Each person using this equipment must read and understand the information in these User Instructions before use. Use of this
equipment by untrained or unqualified persons, or use that is not in accordance with these User Instructions, may adversely affect
product performance and result in sickness or death.
Use For
The Macurco MRS-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.
Do Not Use For
The MRS-485 is not intended for use in hazardous locations or industrial applications such as refineries, chemical plants, etc. Do
not mount the MRS-485 where the normal ambient temperature is below 0°F or exceeds 125°F (-18°C or above 52°C). The MRS-
485 mounts to a Macurco 6-Series detector installed on a 4” x 4”electrical box electricalbox supplied by the contractor.
! WARNING
! WARNING

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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 andresultin sickness or death.
General Description
The Macurco MRS-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 multipointaddressable systems. The Macurco MRS-485 simply plugs into the back of the detectorand a
single screw fastens it in place. The MRS-485 accepts the 4-20mA output and is powered from the same connection as the
detector. The MRS-485 has the ability to interface with Building Automation Systems, Control Panels or other Control Devices that
accept Modbus communications.
Features
The Macurco MRS-485interfaces the detector power and 4-20mA output lines witha mounted connector
The MRS-485 monitors sensor type, gasleveland trouble status communications from any of the Macurco 6-Series detectors
Communication is on a MODBUS 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 standard4” x 4”electrical box
Held in place on the back of the 6-Series detector with a single screw
8 bit dip switch address selector
RS-485 termination uses 4 pin connector with jumper to select termination: The user selects no termination or oneof thetwo
Modbus line termination options
Communications connections include signal (A and B),common and shield terminals
Intended for use in non-hazardous areas suchas parking garages, warehouses or other commercial facilities
Specifications
Power & Current (with detector): 3.25W (max) from 12 to 24 VAC or VDC, 85mA in alarm, 60mA fan relay on and 33mA stand
by @ 24 VDC
Shipping Weight:0.25 lb (0.11 kg)
Size: 3 1/2 x 2 x 13/4 in. (8.9 X 5.1 X 4.4 cm)
Operating Environment: 0°F to 125° F (-18°C to +52°C), 10 to 90% RH non-condensing
Connections: plugs/terminals
Color: Black
Mounting screw and screwdriver included
MRS-485 operates in the RTU Modbus Transmission Mode
Baud Rate: 4800, 9600, 19200 (default), 38400,57600, 115200 bps
Parity: Odd, Even (default) and None
! WARNING

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INSTALLATION AND OPERATING INSTRUCTIONS
The following instructions are intended to serve as a guideline for the use of the Macurco Modbus RS-485 Adapter MRS-485. 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 Service at 1-877-367-7891.
Location
Refer to the user instructions of the specific Macurco 6-Series gas detector to which the MRS-485 will be connected.
Installation
Gas Detection
The Macurco MRS-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 plug from the Macurco 6-Serires gas detector
2. Plug the MRS-485 adapter into the empty socket.
3. Install the provided MRS-485 screw.
4. See the wiring diagram for wire connection.
!
1. The 6-Series detector mounts on a 4”x 4” electricalbox supplied by the contractor.
2. Connect the detector to the control cables with terminal plugs. When making connections, make sure thepower is off.

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3. There are two terminals for the dryalarm 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 section of the
detector User Instructions for details on relay settings.
4. 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.
5. 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 detector OPERATION section of the detector User
Instructions for details on relay settings.
Connection
The Macurco MRS-485output is connected via a fourterminal screw type connector. The MRS-485 adapter is wired in the standard
2W-Modbus circuits definition with selectable built-in terminating resistors at the ends of the RS-485 bus. The power for the MRS-
485 adapter isconnected via a two terminal screw typeconnector,12 to 24 VAC or 12 to 24 VDC and no polarity.
Note: Running the Modbus cable adjacent to or in the same conduit with high voltage wires is not recommended as there may be
interference from the high voltages. Linepolarization should not be required for the MRS-485 but may be required for other devices
on the RS485 line - see manufacturer’s directions.

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Wiring
Signal Wire
A MODBUS over Serial Line Cable should be shielded for best performance. The shield should be connected on each detector at
SHD terminal and connected to a ground terminal or chassis only at one end of the bus. An RS485-MODBUS must use a balanced
pair (for A-B) and a third wire (for the Common). For RS485-MODBUS, Wire Gauge must be chosen sufficiently wide to permit the
maximum length (1000 mor 3281ft). AWG 24 is alwayssufficient for the MODBUS Data. Category 5 cables may operate for RS485-
MODBUS, to a maximum length of 600 m 1968.5 ft. For the balanced pairs used in an RS485-system, wire with a characteristic
impedance of higher than 100 Ohms may be preferred, especiallyfor 19200 and higher baud rates.
Note: It is recommended to always use twisted wires to reduce noise and allow for reliable data communication over greater
distances. Use at least 3-conductor wire with onetwisted pair providing apair for signal (A & B) andcommon (COM) connections.
For best performance use shielded 3-conductor wire with one twisted pair providing a pair for signal (A & B), common (COM) and
shield ground (SHD) connections.
Topology
An RS485-MODBUS configuration without repeater has one trunk cable, along which devices are connected, directly (daisy
chaining) or by short derivation cables. The trunk cable, also named “Bus”, can be long. Its two ends must be connected on Line
Terminations. (see Line Termination - End of Line Resistor section). The use of repeaters between several RS485-MODBUS is also
possible.

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Length
The end to end length of the trunk cable must be limited. The maximum length depends on the baud rate, the cable (Gauge,
Capacitance or Characteristic Impedance), the number of loads on the daisy chain, and the network configuration (2-wire). For a
maximum 9600 Baud Rate and AWG26 (or wider) gauge, the maximum length is 1000m 3281ft. The derivations must be short,
never more than 20m 65.5ft. If a multi-port tap is used with n derivations, each one must respect a maximum length of 40m 131ft
divided by n.
Grounding
The Common circuit(COM) must be connected directly to protectiveground, preferably at one point only forthe entire bus.
Power Wire
All field wiring is completed via modular connectors (provided). After wiring, simply plug the modular connectors into the matching
connectors on the MRS-485. The power connections to the remote mounted detectors should be size AWG18 (minimum) for short
runs. Since Macurcodetectors are rated for operation between 12 and 24 VDC or VAC, the voltage dropbetween the power supply
and the MRS-485 should not be an issue if the recommended power wire gauge guidelines below are followed. The terminals will
accept wire from 16 to 28 AWG. To install a wire, strip back approximately 0.25 in.(6 mm) of insulation, and insert the bare wire into
the terminal. Tighten the screw clamp and ensure that the wire cannot be easily pulled from the connector.
Maximum Run Length
Wire gauge feet meters
18 500 152
16 800 244
14 1250 381
DIP Switches and Addressing
Each MRS-485 (and the partner gas detector) must be configured to a unique address. If there are 10 detectors on the serial line,
then 10 unique addressesmust be used, one for each detector. To set the address use the eight DIP switch positions. For each unit
choose the value from 1 to 247 (see chart) and set the eightswitches to match the address. UP means ON or 1 and DOWN means
OFF or 0. For example, toconfigure a unit as address “50”, set switches “2, 5, 6” (see table) to ON or in the up position (01001100).
See page 11 fora list of applicable addresses and dip-switch settings.

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Changing MRS-485 settings
The DIP switches are to set the Modbus address and are also used to change the MRS-485 settings. Valid Modbus addresses are
between 1 and 247 where switch 1 is the least significant bit (LSB) and switch 8 is the most significant bit (MSB). Address 254 is
used to place the MRS-485 in programming mode and the rest of addresses (248 to 253, 255, 0) are invalid MODBUS addresses.
Programming Mode
When the address is set to 254 the MRS-485 enters programming mode and the LED pattern: Alternating RED/GREEN every 200
milliseconds, indicates that the MRS-485 is ready and waiting for the user to enter new settings using the 8 switches. Using the 8
switches the user canchange the communication settings like baud rate and parity as well as the registration behaviour.
When looking at the switches with the “Address”marking on top, the switches are defined from left to right as:
-Switch 8, switch 7and switch 6 are used to modify baud rate
-Switch 5 and switch 4 are used to modify parity
-Switch 3 and switch 2are used to modify registration mode
-Switch 1 is used to request to save the new settings
Switch 8 Switch 7 Switch 6 Description
OFF OFF OFF Default baud rate (19200 Bd)
OFF OFF ON 4800 Bd
OFF ON OFF 9600 Bd
OFF ON ON 19200 Bd (Default value)
ON OFF OFF 38400 Bd
ON OFF ON 57600 Bd
ON ON OFF 115200 Bd
ON ON ON Do not change
Switch 5 Switch 4 Description
OFF OFF Default parity (EVEN)
OFF ON Parity is ODD
ON OFF Parity is NONE
ON ON Do not change
Registration mode can be latched or unlatched. MRS-485 is always using data from a valid registration but when registration is
latched it will also compare the saved value with the new one and set a flag if it is different. This way, by reading the flag, you can
check if it is a different sensortype and you always get dataabout the sensor present.
Switch 3 Switch 2 Description
OFF OFF Default registration mode (Registration not latched)
OFF ON Registration not latched (Default value)
ON OFF Registration is latched
ON ON Do not change

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Set the switches to the desired value and then set switch 1 to ON and then OFF and the new settings will besaved in EERPOM.
The result of saving operation is displayed on LED: Alternating RED/OFF every 200 milliseconds indicates that saving new settings
failed and Alternating GREEN/OFF every 200 milliseconds indicates that saving new settings passed. Once the new settings have
passed, set the address for the device using the Address switches.
Line Termination - End of Line Resistor
The MRS-485 adapter is wired in the standard2W-Modbus circuits definitionwith selectable built-in terminating resistors at the ends
of the RS-485 bus. The MRS-485 provides integral termination for end of line resistors (EOL). The MRS-485 termination uses 4 pin
connector with jumper to select termination: The user selects no termination or one of the two Modbus line termination options. The
MRS485 has two line termination options providedonboard that should cover most situations.
Place the EOL jumper on one of the following positions:
1 = 100 ohm
2 = 120 ohm
N = No termination (default)
If Line Termination requirements are differentthan those provided then the line termination will need to be provided by the installer.

1 = 1
2 = 2
3 = 1, 2
4 = 3
5 = 1, 3
6 = 2, 3
7 = 1, 2, 3
8 = 4
9 = 1, 4
10 = 2, 4
11 = 1, 2, 4
12 = 3, 4
13 = 1, 3, 4
14 = 2, 3, 4
15 = 1, 2, 3, 4
16 = 5
17 = 1, 5
18 = 2, 5
19 = 1, 2, 5
20 = 3, 5
21 = 1, 3, 5
22 = 2, 3, 5
23 = 1, 2, 3, 5
24 = 4, 5
25 = 1, 4, 5
26 = 2, 4, 5
27 = 1, 2, 4, 5
28 = 3, 4, 5
29 = 1, 3, 4, 5
30 = 2, 3, 4, 5
31 = 1, 2, 3, 4, 5
32 = 6
33 = 1, 6
34 = 2, 6
35 = 1, 2, 6
36 = 3, 6
37 = 1, 3, 6
38 = 2, 3, 6
39 = 1, 2, 3, 6
40 = 4, 6
41 = 1, 4, 6
42 = 2, 4, 6
43 = 1, 2, 4, 6
44 = 3, 4, 6,
45 = 1, 3, 4, 6
46 = 2, 3, 4, 6
47 = 1, 2, 3, 4, 6
48 = 5, 6
49 = 1, 5, 6
50 = 2, 5, 6
51 = 1, 2, 5, 6
52 = 3, 5, 6
53 = 1, 3, 5, 6
54 = 2, 3, 5, 6
55 = 1, 2, 3, 5, 6
56 = 4, 5, 6
57 = 1, 4, 5, 6
58 = 2, 4, 5, 6
59 = 1, 2, 4, 5, 6
60 = 3, 4, 5, 6
61 = 1, 3, 4, 5, 6
62 = 2, 3, 4, 5, 6
63 = 1, 2, 3, 4, 5, 6
64 = 7
65 = 1, 7
66 = 2, 7
67 = 1, 2, 7
68 = 3, 7
69 = 1, 3, 7
70 = 2, 3, 7
71 = 1, 2, 3, 7
72 = 4, 7
73 = 1, 4, 7
74 = 2, 4, 7
75 = 1, 2, 4, 7
76 = 3, 4, 7
77 = 1, 3, 4, 7
78 = 2, 3, 4, 7
79 = 1, 3, 4, 7
80 = 5, 7
81 = 1, 5, 7
82 = 2, 5, 7
83 = 1, 2, 5, 7
84 = 3, 5, 7
85 = 1, 3, 5, 7
86 = 2, 3, 5, 7
87 = 1, 2, 3, 5, 7
88 = 4, 5, 7
89 = 1, 4, 5, 7
90 = 2, 4, 5, 7
91 = 1, 2, 4, 5, 7
92 = 3, 4, 5, 7
93 = 1, 3, 4, 5, 7
94 = 2, 3, 4, 5, 7
95 = 1, 2, 3, 4, 5, 7
96 = 6, 7
97 = 1, 6, 7
98 = 2, 6, 7
99 = 1, 2, 6, 7
100 = 3, 6, 7
101 = 1, 3, 6, 7
102 = 2, 3, 6, 7
103 = 1, 2, 3, 6, 7
104 = 4, 6, 7
105 = 1, 4, 6, 7
106 = 2, 4, 6, 7
107 = 1, 2, 4, 6, 7
108 = 3, 4, 6, 7
109 = 1, 3, 4, 6, 7
110 = 2, 3, 4, 6, 7
111 = 1, 2, 3, 4, 6, 7
112 = 5, 6, 7
113 = 1, 5, 6, 7
114 = 2, 5, 6, 7
115 = 1, 2, 5, 6, 7
116 = 3, 5, 6, 7
117 = 1, 3, 5, 6, 7
118 = 2, 3, 5, 6, 7
119 = 1, 2, 3, 5, 6, 7
120 = 4, 5, 6, 7
121 = 1, 4, 5, 6, 7
122 = 2, 4, 5, 6, 7
123 = 1, 2, 4, 5, 6, 7
124 = 3, 4, 5, 6, 7
125 = 1, 3, 4, 5, 6, 7
126 = 2, 3, 4, 5, 6, 7
127 = 1, 2, 3, 4, 5, 6, 7
128 = 8
129 = 1, 8
130 = 2, 8
131 = 1, 2, 8
132 = 3, 8
133 = 1, 3, 8
134 = 2, 3, 8
135 = 1, 2, 3, 8
136 = 4, 8
137 = 1, 4, 8
138 = 2, 4, 8
139 = 1, 2, 4, 8
140 = 3, 4, 8
141 = 1, 3, 4, 8
142 = 2, 3, 4, 8
143 = 1, 2, 3, 4, 8
144 = 5, 8
145 = 1, 5, 8
146 = 2, 5, 8
147 = 1, 2, 5, 8
148 = 3, 5, 8
149 = 1, 3, 5, 8
150 = 2, 3, 5, 8
151 = 1, 2, 3, 5, 8
152 = 4, 5, 8
153 = 1, 4, 5, 8
154 = 2, 4, 5, 8
155 = 1, 2, 4, 5, 8
156 = 3, 4, 5, 8
157 = 1, 3, 4, 5, 8
158 = 2, 3, 4, 5, 8
159 = 1, 2, 3, 4, 5, 8
160 = 6, 8
161 = 1, 6, 8
162 = 2, 6, 8
163 = 1, 2, 6, 8
164 = 3, 6, 8
165 = 1, 3, 6, 8
166 = 2, 3, 6, 8
167 = 1, 2, 3, 6, 8
168 = 4, 6, 8
169 = 1, 4, 6, 8
170 = 2, 4, 6, 8
171 = 1, 2, 4, 6, 8
172 = 3, 4, 6, 8
173 = 1, 3, 4, 6, 8
174 = 2, 3, 4, 6, 8
175 = 1,2, 3, 4, 6, 8
176 = 5, 6, 8
177 = 1, 5, 6, 8
178 = 2, 5, 6, 8
179 = 1, 2, 5, 6, 8
180 = 3, 5, 6, 8
181 = 1, 3, 5, 6, 8
182 = 2, 3, 5, 6, 8
183 = 1, 2, 3, 5, 6, 8
184 = 4, 5, 6, 8
185 = 1, 4, 5, 6, 8
186 = 2, 4, 5, 6, 8
187 = 1, 2, 4, 5, 6, 8
188 = 3, 4, 5, 6, 8
189 = 1, 3, 4, 5, 6, 8
190 = 2, 3, 4, 5, 6, 8
191 = 1, 2, 3, 4, 5, 6, 8
192 = 7, 8
193 = 1, 7, 8,
194 = 2, 7, 8,
195 = 1, 2, 7, 8
196 = 3, 7, 8
197 = 1, 3, 7, 8
198 = 2, 3, 7, 8
199 = 1, 2, 3, 7, 8
200 = 4, 7, 8,
201 = 1, 4, 7, 8
202 = 2, 4, 7, 8
203 = 1, 2, 4, 7, 8
204 = 3, 4, 7, 8
205 = 1, 3, 4, 7, 8
206 = 2, 3, 4, 7, 8
207 = 1, 2, 3, 4, 7, 8
208 = 5, 7, 8
209 = 1, 5, 7, 8
210 = 2, 5, 7, 8
211 = 1, 2, 5, 7, 8
212 = 3, 5, 7, 8
213 = 1, 3, 5, 7, 8
214 = 2, 3, 5, 7, 8
215 = 1, 2, 3, 5, 7, 8
216 = 4, 5, 7, 8
217 = 1, 4, 5, 7, 8
218 = 2, 4, 5, 7, 8
219 = 1, 2, 4, 5, 7, 8
220 = 3, 4, 5, 7, 8
221 = 1, 3, 4, 5, 7, 8
222 = 2, 3, 4, 5, 7, 8
223 = 1, 2, 3, 4, 5, 7, 8
224 = 6, 7, 8
225 = 1, 6, 7, 8
226 = 2, 6, 7, 8
227 = 1, 2, 6, 7, 8
228 = 3, 6, 7, 8
229 = 1, 3, 6, 7, 8
230 = 2, 3, 6, 7, 8
231 = 1, 2, 3, 6, 7, 8
232 = 4, 6, 7, 8
233 = 1, 4, 6, 7, 8
234 = 2, 4, 6, 7, 8
235 = 1, 2, 4, 6, 7, 8
236 = 3, 4, 6, 7, 8
237 = 1, 3, 4, 6, 7, 8
238 = 2, 3, 4, 6, 7, 8
239 = 1, 2, 3, 4, 6, 7, 8
240 = 5, 6, 7, 8
241 = 1, 5, 6, 7, 8
242 = 2, 5, 6, 7, 8
243 = 1, 2, 5, 6, 7, 8
244 = 3, 5, 6, 7, 8
245 = 1, 3, 5, 6, 7, 8
246 = 2, 3, 5, 6, 7, 8
247 = 1, 2, 3, 5, 6, 7, 8
254 = 2, 3, 4, 5, 6, 7, 8

Power Up
The Macurco 6-Series detector cycles through an internal self-test cycle for the first minute that it is powered. The unit will execute
the test cycle any time power is dropped and reapplied (i.e. powerfailure). During the self-test cycle the unit will display the firmware
version number, then count down from 60 to 0 (if the display setting is “On”) and finally go into normal operation. The alarm relay will
be activated for 10 seconds and the fan relay for 60 seconds during the power-up cycle unless the “Power Up Test” (PUt) option is
OFF. The indicator light (LED) will flash green during the self-test cycle. At the end of the 1 minute cycle, the unit will take its first
sample of the air and the indicator light will turn solid green.
The MRS-485 is anadapterwhich allows the reading ofa 6-Series gasdetector over a Modbus interface. To achieve this, the MRS-
485 will monitor the 4-20 mA current output of the detector. At power up and during its warm-up period, the 6-Series detector will
communicate its sensor type over the 4-20 current output using a custom protocol. The MRS-485 will automatically register each 6-
Series detector as it is programmed with information about all the detectors to which it can be connected. The MRS-485 will use this
information to determine the gas level sensed by the 6-Series detector by measuring the 4-20 mA current-loop output during normal
operation of the detector.
4-20mA Test Points
The MRS-485 has two Test Points labeled 1 and 2. These are provided to test the 4-20mA analog output directly fromthe detector,
using a meter and probes, withouthaving to remove the MRS-485from the detector. See the Testing section for more detail.
Operation
1. With the display function turned “On”, the 6-Series detector will show the current concentration of gas or “0” (zero) in clean air.
When the gas concentration reaches the Fan Relay setting the display will flash back and forth between “FAn” and that
concentration. With the display function turned ”Off”, the display does not show the gas concentration, but will show “FAn” as
long as the fan relay is activated.
2. With the display function turned “On” and the gas concentration reaching the Alarm Relay setting, the display will flash back and
forth between “ALr” and that concentration. The buzzer will sound indicating “Alarm” if the buzzer is turned “On”. With the
display function turned off the display does not show the gas concentration, but will show “ALr” when the Alarm relay is
activated.
3. With the 4-20 mA function turned “On” and the gas concentration climbing, the 4-20 mA signal will ramp up corresponding to the
concentration. The display will show “FAn” and “ALr” and sound as outlined above. The MRS-485 will monitor the 4-20 mA
current output of the detector. The MRS-485 has a Tricolor LED (RED, GREEN and AMBER) which is used to display the
status.
Normal Operation
1. When the LED is solid GREEN, operation is normal, the MRS-485 knows the detector type, no errors are detected and no
MODBUS data arebeing received or transmitted over the RS-485 line.
2. When the LED is GREEN with random bursts of AMBER, operation is normal and now data are being received or transmitted
over the RS-485 line. The AMBER LED will come on anytime that there is data traffic.

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Onboard Diagnostics
Unknown Sensor Code
GREEN/OFF Alternating every 500 milliseconds - The MRS-485 doesn’t know the detector type, no MODBUS communications is in
progress and no errors are detected.
To correct this condition:
1. Disconnect the power line from the MRS-485.
2. Disconnect the MODBUS line from the MRS-485.
3. Re-connect the Modbus Line tothe MRS-485.
4. Re-connect the power line to the MRS-485.
Error Codes
Solid RED - The MRS-485 detectedan error and no MODBUS communications are in progress.
RED with random bursts of AMBER - The MRS-485 detected an error and AMBER is displayed when data are received or
transmitted over the RS-485 line.
There are a number of conditions which are signalized in this way:
-Current EEPROM Settings not initialized
-Current EEPROM Settings havebad checksum
-Factory EEPROM Settingsnot initialized
-Factory EEPROM Settings have bad checksum
-Unknown Sensor exponentvalue
-Watchdog reset
-Loaded Factory EEPROM Settings in EEPROM Current Settings
-Latched sensor typedifferent than registered sensor type
-Unknown sensor type because registration failed
Dip Switch Settings Codes
RED/GREEN Alternating every 200 milliseconds indicates that MRS-485 is in programming mode and waiting for user to enter new
settings using the 8 switches.
RED/OFF alternating every 200 milliseconds indicatesthat saving new settings failed.
GREEN/OFF alternating every 200 milliseconds indicates that saving new settings passed.
RED/OFF alternating every 500 milliseconds indicatesthat selected MODBUS address is not an accepted value.

14
6-Series Testing
General
The Macurco MRS-485 adapter converts the 4-20mA analog signal from Macurco 6-Series type detectors to a digital signal for use
with multipoint addressable systems. The 6-Series test procedures may be used to ensure that the MRS-485 accepts the 4-20mA
output for the Modbus communications. All 6-Series detectors are factory calibrated and 100%tested for proper operation. The units
also perform a regular automatic self-test during normal operation. If the unit detects an improper voltage or inoperable component,
it will default into Error mode. In this error mode, the Fan and Alarm relays will be activated, the4-20 mA output will go to 24 mA, the
unit will display the error code and the buzzer will chirp intermittently.
Operation Test
Normally this will be the only test required for the 6-Series detectors and is the recommended way to test the unit or units after
installation. Check that thegreen detector operating LED light is illuminated continuously. If not, do not proceed with the tests. If the
unit is in error mode contact your local representative or Macurco technical service representative for information on resolving the
problem.
1. Remove the single screw in the middle of the front cover of the 6-Series detector.
2. Remove the front cover.
3. Observe the LED light on the frontof the 6-Series detectors.
4. If the light is solid green proceed to step 6.
5. If the light is offor flashing Green, refer to the Generalsection above.
6. Locate the switch labeled ENTER/TEST onthe left side of the printedcircuit board. Press the Test switch once.
7. The 6-Series detector will step through a cycle test:
a. The display progresses through the bUZ (Buzzer Test) Art (alarm relay test), Frt (fan relay test) then 42t (4-20 mA output
test).
b. Make sure that the settings are “on”or not disabled “diS”.
c. During the first 10 seconds of the test cycle, the display will show BUZ and set off the audible buzzer
d. The alarm relay will be closed, so any devices connected to that relaywill be tested.
e. The Fan relay will be activated for the next 1 minute of the test, so if the fan circuits are wired in the normal manner, the fan
should run.
f. The 4-20mA output will then ramp up from 4 to 16 mA over the next 130 seconds of the test, so if the circuit is wired in the
normal manner, the control panel or building automation system shouldrespond.
g. At the end of the test cycle, the light will turn green and be on steady (Normal Operation), the fan & alarm relay will be in
standby mode and the 4-20 mA output will return to 4 mA (in clean air).
8. When testing is completed reassemblethe unit or units.

15
Manual Operation Test
This option gives the user the opportunity to manually initiate an individual test for each relay, the analog output and the sensor
response to gas. From normal operation mode press the Next button 3 times to get to the Test Mode (tSt). Press the Enter button
once to get into the Test Menu. Press the Next button to scroll through the four test options and press Enter to initiate the selected
test. Note that if the relay or 4–20 mA output has beendisabled, the test selection will not be displayed in the test menu.
Art - Alarm Relay Test, 10 seconds
Frt - Fan Relay Test, 60 seconds
42t - 420 loop test,25 seconds
MAINTENANCE
The MRS-485 does not require regular maintenance. All maintenance and repair of products manufactured by Macurco are to be
performed at the appropriate Macurco manufacturing facility. Macurco does not sanction any third-party repair facilities.
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 result in sickness ordeath.
CAUTION
Avoid the use of harsh cleaning materials, abrasives and other organic solvents. Such materials may permanently scratch the
surfaces and damage the LEDs labels or instrument housing.
Cleaning
Cleaning of the external surfaces is best carried out using a damp cloth with a mild detergent or soap. Use a vacuum cleaner with
soft brush to removedust or contamination. Donot blow out the sensor with compressed air.
! WARNING

16
MACURCO FIXED GAS DETECTION PRODUCTS LIMITED WARRANTY
Macurco warrants the MRS-485 adapter will be free from defective materials and workmanship for a period of two (2) years from
date of manufacture (indicated on the cover of the MRS-485), provided it is maintained and used in accordance with Macurco
instructions and/or recommendations. If any component becomes defective during the warranty period, it will be replaced or repaired
free of charge, ifthe unit isreturned in accordance with the instructions below. This warranty doesnot apply tounits that have been
altered or had repair attempted, or that have been subjected to abuse, accidental or otherwise. The above warranty is in lieu of all
other express warranties, obligations or liabilities. THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
PARTICULAR PURPOSE ARE LIMITED TO A PERIODOF TWO (2) YEARS FROM THE PURCHASE DATE. Macurco shallnot be
liable for any incidental or consequential damages for breach of this or any other warranty, express or implied, arising out of or
related to the use of said gas detector. Manufacturer or its agent’s liability shall be limited to replacement or repair as set forth
above. Buyer’s sole and exclusive remedies are return of the goods and repayment of the price, or repair and replacement of non-
conforming goods or parts.
Manufactured by Aerionics, Inc.
Sioux Falls, SD
Email: [e-mail]
Phone: [phone]
Rev 06.29.2015
© Aerionics 2015. All rights reserved.
Macurco is a trademark of Aerionics, Inc.

Macurco™ Modbus® RS-485 Adaptador MRS-485
Instruccionespara el usuario
IMPORTANTE:MantengaestasInstruccionescomoreferencia

2
TABLA DE CONTENIDO
INFORMACIÓN GENERAL DE SEGURIDAD 3
Uso previsto 3
Lista de Advertenciasy Precauciones 3
INSTRUCCIONES DE USO Y LIMITACIONES 3
Utilice Para 3
No utilice para 3
Descripción General 4
Características 4
Especificaciones 4
INSTRUCCIONES DE INSTALACIÓN Y OPERACIÓN 5
Ubicación 5
Instalación 5
Vista trasera desarrollada 5
Vista frontal desarrollada 6
Conexión 6
Cableado 7
Cable de señal 7
Topología 7
Diagrama de conexión típica 7
Longitud 8
Toma de tierra 8
Energía 8
Interruptores DIP y direccionamiento 8
Figura del interruptor DIP 8
Ajustes 9
Programación 9
Teminación de línea 10
Detalle de MRS-485 10
Tabla de configuración del interruptor Dip 11
Carga 12
Puntos de prueba 4-20mA 12
Operación 12
Operación Normal 12
Diagnósticos a bordo 13
Códigos de error 13
Códigos deconfiguración del interruptor DIP 13
Pruebas 14
General 14
Prueba de funcionamiento 14
Prueba manual de funcionamiento 15
MANTENIMIENTO 15
Limpieza 15
GARANTÍA DE LOS PRODUCTOS MARUCO DE DETECCIÓN DE GAS 16

4
INFORMACIÓNGENERAL DESEGURIDAD
Usoprevisto
El adaptador Macurco MRS-485 es un accesorio utilizado para convertir la señal analógica 4-20 mA de los detectores Macurco 6-
Series auna señal digitalpara su uso con los sistemas direccionables multipunto. El Macurco MRS-485 sólo se conectaa la parte
posterior del detector y es sostenido en su lugar por un solo tornillo. El MRS-485 acepta la salida 4-20 mA y, al igual que el
detector, se alimenta de la misma conexión. El MRS-485 tiene la capacidad de interactuar con lossistemas de automatizaciónde
edificios, con los paneles de control o con otros dispositivos de control que acepten las comunicaciones Modbus.
Lista de advertencias y precauciones en estas instrucciones para el usuario
! ADVERTENCIA
Antes de usareste equipo, cada persona, que lo utilice, debe leer y entender la información en estas instrucciones El uso de
este equipo por personas no capacitadas o no calificadas, o el uso sinseguir las instrucciones para elusuario,puedeafectar
negativamente elrendimiento del producto, e incluso ocasionar enfermedad o muerte.
Este equipo no funciona adecuadamenteen una temperatura por debajo de los 0 ° F o por encima de los 125 ° F (-18 ° C o
porencimade los 52 ° C).Usar el detector fuera de este rango de temperatura puede afectar negativamente el desempeño del
producto, e incluso ocasionar enfermedado muerte.
No desarme la unidad ni intente reparar o modificar ningunode loscomponentes de este instrumento. Este instrumento
no contiene ninguna pieza que el usuario pueda reparar y la sustitución de componentes puede afectar el rendimiento
del producto, e incluso ocasionar enfermedad omuerte.
INSTRUCCIONES DEUSO YLIMITACIONES
! ADVERTENCIA
Antes de usar este equipo, cada persona que lo utilice, debe leer y entender la información en estas Instrucciones. El uso de
este equipo por personas no capacitadas o no calificadas, o el uso sin seguir las instrucciones para el usuario, puede afectar
negativamente el rendimiento del producto, e incluso ocasionar enfermedad o muerte.
Utilice Para
El adaptador Maruco MRS-485 convierte la salida analógica del Macurco 6-Series de 4-20 mA a una salida digital para los
sistemas de red direccionables. ElMacurco6-Series es unafamilia de detectores de gas duales, de controladores y de
transductores totalmente programables y de baja tensión para los sistemas de automatización de edificios (BAS, por sus
siglas en inglés), para la calefacción, la ventilación y elaire acondicionado (HVAC, por sus siglas en inglés) y para incendios y
seguridad. Los detectores 6-Series se utilizan para medir la concentración de varios gases: monóxido de carbono, metano,
propano, hidrógeno, dióxido de nitrógeno y otros gases; y para proporcionar una retroalimentación y un control automático que
ayude a garantizar un ambiente seguro
No utilice para
El MRS-485 noestá diseñado para su uso en lugares peligrosos o para aplicaciones industriales tales como en refinerías, plantas
químicas, etc. Noinstaleel MRS-485 donde la temperatura ambientenormal sea inferior a los 0 °F o superior alos 125 ° F (-18 ° C
o superior a los 52 ° C). El MRS-485 se instala en un detector Macurco 6-Series instalado en una caja eléctrica de 4” x 4"
suministrada por el contratista.

5
! ADVERTENCIA
Este equipo puede no funcionar adecuadamente en una temperatura por debajo de los 0 ° F o por encima de los 125 ° F (-18 ° C o
superior a los 52 ° C). Usar el detector fuera de este rango de temperatura puede afectar negativamente el desempeño del
producto, e incluso ocasionar enfermedad o muerte.
Descripción General
El adaptador Macurco MRS-485 es un accesorio utilizado para convertir la señal analógica 4-20 mA de los detectores Maruco 6-
Series a una señal digital para su uso con los sistemas direccionables multipunto. El Macurco MRS-485 sólo se conectaa la parte
posterior del detector y se sostiene en su lugar por un solo tornillo. El MRS-485 acepta la salida 4-20 mA y, al igual
que el detector, se alimenta de la misma conexión. El MRS-485 tiene la capacidad de interactuar con los sistemas
de automatización de edificios, con los paneles de control o con otros dispositivos de control que acepten las
comunicaciones Modbus.
Características
El Macurco MRS-485 enlaza la energía del detector y las líneas de salida 4-20mA con un conector ya instalado.
Los monitores MRS-485 de tipo sensor para sondear los niveles de gas, losestátus de los problemas de cualquiera de los
detectores Maruco 6-Series.
La comunicación está sobre una línea serie MODBUS con una interfaz eléctrica "de dos cables" de acuerdo a los
estándares EIA / TIA-485utilizados.
Modo de transmisión RTU
De tipo comercialrecubierto, para proteger y ayudar a los electrónicos
El LEDTricolor indica el estado de energía, de prueba y de comunicación
Se instala detrás del detector en el interior de una caja eléctricaestándar 4"x 4"
Mantenga el detector 6-Series con un solo tornillo en la parte posterior
Selector del interruptor DIP de 8bits del direccionador
La terminación RS-485 utiliza un conector de 4 pines con un puente para seleccionarla: El usuario no selecciona ninguna
terminación o selecciona una de las dos
Opciones de terminación de la línea Modbus
Las conexiones de comunicación incluyen terminales de señal (Ay B), comunes y de escudo
Diseñado para su uso en zonas no peligrosas tales como estacionamientos, almacenes u otros establecimientos comerciales
Especificaciones
Energía y corriente (con un detector): 3.25W (máximo) de 12 a 24 VAC o VDC, 85mA en estado de alarma, 60mA en el
relevador del ventilador y 33mA en el soporte de @ 24 VDC
Peso envío:0,25 libras (0,11 kg)
Tamaño: 3 1/2 x2 x 1 3/4 pulgadas (8,9 X 5,1 X 4,4 cm)
Medio operativo: De 0 ° F a 125 ° F (-18 ° C a + 52 ° C), de 10a 90% de humedad relativa sincondensación
Conexiones: enchufes / terminales
Color: Negro
Tornillo de instalación y desarmador incluidos
El MRS-485 opera en el modode transmisión Mosbus RTU
Velocidad de transferencia: 4800, 9600, 19200 (predeterminado), 38.400, 57.600, 115.200 bps
Paridad: Impar, Par (predeterminado)y Ninguno