Bacharach MVR-300 User manual

MVR-300™
Refrigerant Gas Detector
for Occupied Spaces
User Manual
Installation ●Operation ● Configuration ● Troubleshooting
P/N: 6203-9000
August 2016
Version 1
Product Leadership •Training •Service •Reliability
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MVR-300™ Refrigerant Gas Detector
2 P/N: 6203-9000 Version 1
WARRANTY POLICY
Bacharach, Inc. warrants this detector, excluding sensors, to be free from defects in materials and workmanship for a period of 12
months from the date of purchase by the original owner. The sensor has a pro-rated warranty period of 12 months. If the product
should become defective within this warranty period, we will repair or replace it at our discretion.
The warranty status may be affected if the detector has not been used and maintained per the instructions in this manual or has
been abused, damaged, or modified in any way. This detector is only to be used for purposes stated herein. The manufacturer is not
liable for auxiliary interfaced equipment or consequential damage.
Due to ongoing research, development, and product testing, the manufacturer reserves the right to change specifications without
notice. The information contained herein is based on data considered accurate. However, no warranty is expressed or implied
regarding the accuracy of this data.
All goods must be shipped to the manufacturer by prepaid freight. All returned goods must be pre-authorized by obtaining a return
merchandise authorization (RMA) number. Visit for an RMA number and procedures required for product
transport.
NOTICES
This manual is subject to copyright protection; all rights are reserved under international and domestic copyright laws. This manual
may not be copied or translated, in whole or in part, in any manner or format, without the written permission of Bacharach, Inc.
All software utilized and/or distributed by Bacharach is subject to copyright protection. All rights are reserved. No party may use or
copy such software in any manner or format, except to the extent that Bacharach grants them a license to do so. If this software is
being loaded onto more than one computer, extra software licenses must be purchased.
MVR-300™ is a trademark of Bacharach, Inc. All rights reserved.
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MVR-300™ Refrigerant Gas Detector
P/N: 6203-9000 Version 1 3
TABLE OF CONTENTS
SECTION 1. SAFETY ............................................................................................................................5
1.1 Definition of Alert Icons..............................................................................................................5
1.2 General Safety Statements .......................................................................................................5
1.3 Safe Connection of Electrical Devices ......................................................................................6
SECTION 2. DESCRIPTION..................................................................................................................7
2.1 Product Overview ......................................................................................................................7
2.2 Intended Use .............................................................................................................................7
2.3 Design Features ........................................................................................................................7
2.4 Components Overview..............................................................................................................8
SECTION 3. INSTALLATION..............................................................................................................10
3.1 General Information for Installation .........................................................................................10
3.2 Mechanical Installation............................................................................................................10
3.3 Configuration ...........................................................................................................................12
3.4 Electrical Installation................................................................................................................14
SECTION 4. OPERATION...................................................................................................................17
4.1 Start-up....................................................................................................................................17
4.2 Alarm Management Function and Configuration.....................................................................17
4.2.1 Default Alarm Function...............................................................................................17
4.2.2 Alarm Delay – Switches 2 and 3 ................................................................................18
4.2.3 Failsafe – Switch 4 .....................................................................................................20
4.2.4 Alarm 2 Relay – Switch 5 ...........................................................................................20
4.2.5 Latching Alarm State – Switch 6 ................................................................................20
4.2.6 Buzzer Disable – Switch 7..........................................................................................20
4.3 Other Switch Configurations....................................................................................................21
4.3.1 Reset (Cycle Power) -Switch 1................................................................................21
4.3.2 Reset to Factory Default Values -Switch 8...............................................................21
4.4 Operation of Magnetic Switches, Buzzer, and LED ................................................................22
SECTION 5. MAINTENANCE..............................................................................................................23
5.1 Maintenance Intervals .............................................................................................................23
5.2 Adjustments.............................................................................................................................23
5.2.1 Introduction.................................................................................................................23
5.2.2 General Procedure .....................................................................................................24
5.2.3 Zero Adjustment.........................................................................................................25
5.2.4 Span Adjustment ........................................................................................................25
5.2.5 Bump Test ..................................................................................................................26
5.3 Troubleshooting.......................................................................................................................26
5.3.1 Failed Span Adjustment .............................................................................................26
5.3.2 Hexadecimal Format ..................................................................................................27
5.3.3 Fault Conditions..........................................................................................................28
5.3.4 Fatal Faults.................................................................................................................29
5.3.5 Critical Faults..............................................................................................................29
5.3.6 Negative Gas Fault.....................................................................................................29
5.3.7 Non-Critical Faults......................................................................................................29
5.4 Replacing the Sensor Module .................................................................................................30
5.5 Cleaning the Detector..............................................................................................................31
SECTION 6. SENSOR PRINCIPLE.....................................................................................................32
SECTION 7. DISPOSING OF THE DETECTOR.................................................................................33
SECTION 8. TECHNICAL DATA.........................................................................................................34
8.1 Approvals.................................................................................................................................34
8.2 Specifications for Modbus RTU Digital Communication over RS-485 ....................................34
8.3 Power Supply and Relay Specifications..................................................................................34
8.4 Wiring Specifications ...............................................................................................................34
8.5 Physical Specifications............................................................................................................35
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8.6 Environmental Specifications ..................................................................................................35
8.7 Sensor Specifications..............................................................................................................35
8.8 Default Alarm Levels ...............................................................................................................35
8.9 Modbus Registers....................................................................................................................36
8.9.1 Read Device Identification..........................................................................................36
8.9.2 Analog Input Registers...............................................................................................36
8.9.3Analog Output Registers ............................................................................................38
8.9.4 Input Status Flags.......................................................................................................39
8.9.5 Output Status Flags....................................................................................................40
SECTION 9. ORDERING INFORMATION ..........................................................................................42
9.1 MVR-300 Refrigerant Leak Detector Configurations...............................................................42
9.2 MVR-300 Refrigerant Leak Detector Configurations (UK Version).........................................42
9.3 Accessories .............................................................................................................................43
SECTION 10. CUSTOM UK BACK BOXES AND FACEPLATES .......................................................44
10.1 Introduction to UK Version.......................................................................................................44
10.2 Hardware Overview – UK Version...........................................................................................44
10.3 Using Optional Metal Tabs......................................................................................................45
10.4 Electrical Installation – UK Version .........................................................................................45
10.5 Customizing Face Plates.........................................................................................................46
10.6 Calibration................................................................................................................................47
SECTION 11. DECLARATION OF CONFORMITY...............................................................................49
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MVR-300™ Refrigerant Gas Detector
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SECTION 1. SAFETY
1.1 Definition of Alert Icons
The following alert icons are used in this document to highlight areas of the associated text that require a
greater awareness by the user.
Alert Icon Description
DANGER
Indicates an imminently hazardous situation which, if not avoided, will
result in death or serious injury.
WARNING
Indicates a potentially hazardous situation which, if not avoided, could
result in death or serious injury.
WARNING
Indicates a potential electrical shock hazard which, if not avoided, could
result in death or serious injury.
CAUTION
Indicates a potentially hazardous situation which, if not avoided, could
result in physical injury or damage to the product or environment. It may
also be used to alert against unsafe practices.
NOTICE
Indicates additional information on how to use the product.
1.2 General Safety Statements
•Before using this product, carefully read and strictly follow the instructions in the manual.
•Use the product only for the purposes specified in this document and under the conditions listed.
•Ensure that product documentation is retained, made available, and appropriately used by anyone
operating the product.
•Comply with all local and national laws, rules, and regulations associated with this product.
•Only trained and competent personnel may use this product.
•Only trained and competent personnel may inspect, repair and maintain the product as detailed in this
manual. Maintenance that is not detailed in this manual must be completed by Bacharach or
personnel qualified by Bacharach.
•Use only genuine Bacharach spare parts and accessories. Otherwise, operation may be impaired.
•Only operate the product within the framework of a risk-based alarm signaling concept.
•
CAUTION
REFRIGERANT SUFFOCATION RISK: Large refrigerant leaks into occupied spaces
can reach concentrations that pose a suffocation risk to the occupants. While the MVR-
300 can be used to detect refrigerant leaks well below those concentrations, it is not
designed as a stand-alone safety device. Safety of the occupants must take a system
design approach including ventilation, detection, early warning, mitigation, and design
redundancy among other considerations.
•
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1.3 Safe Connection of Electrical Devices
Before connecting this detector to electrical devices not mentioned in this manual, consult the
manufacturer or a qualified professional.
NOTICE
The sensor must be connected by a marked, suitably located and easily reached switch
or circuit-breaker as means of disconnection.
NOTICE
If replacement of either main power fuse is required, use only a TR5 Radial 3.15A 250V
slow fuse (Littlefuse 372 1315 0001 or equivalent).
CAUTION
Wiring must be in compliance with national and local wiring codes.
CAUTION
RS-485 signal cable must be insulated to the highest voltage level in the system. Protect
the RS-485 signal cable by using the supplied installation kit.
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MVR-300™ Refrigerant Gas Detector
P/N: 6203-9000 Version 1 7
SECTION 2. DESCRIPTION
2.1 Product Overview
The Bacharach MVR-300 continuously checks the ambient air of occupied spaces for refrigerant leaks.
The detector is for indoor applications. It is housed in an ABS enclosure that fits into most 2-gang
electrical back boxes (not included).
NOTICE
The MVR-300 is designed for use in 2-gang back boxes with a minimum depth of 47 mm
(1.9”). Metal United Kingdom (UK) back boxes are also supported, but require a special
UK version of the MVR-300, slightly modified installation, and a customized faceplate
(not supplied by Bacharach). Otherwise, the UK version is functionally the same. Refer
to Chapter 10 for more information on the UK version and its differences.
Figure 1. MVR-300 with Examples of Supported 2-gang Back Boxes
Gas alarms and status messages are indicated visually by a 3-colored LED and audibly by a buzzer. In
case of an alarm and/or fault, relays switch (for example, to shut-off valves or to activate alarm devices).
2.2 Intended Use
•Checks ambient air of occupied spaces for refrigerant leaks
•Intended for indoor applications
•ABS enclosure fits into most 2-gang electrical back boxes (not included)
•Can be operated as a stand-alone detector or connected to a BMS/BAS (Building
Management/Building Automation) System
•Designed to be installed in non-classified, non-hazardous, permanent locations.
2.3 Design Features
•Powered by 100 to 240 VAC, 50/60 Hz
•Gas alarms and status messages are indicated visually by a 3-colored LED and audibly by a buzzer
•In case of an alarm and/or fault, relays can switch shut-off valves, alarm devices, or indicators at a
BMS/BAS
•Measured gas concentration, status signals and configuration information are accessible via the
Modbus RTU interface (see Section 8.9 on page 35)
•Can be calibrated and maintained non-intrusively using a magnetic wand
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MVR-300™ Refrigerant Gas Detector
8 P/N: 6203-9000 Version 1
2.4 Components Overview
Figure 2. MVR-300 Components (Front)
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P/N: 6203-9000 Version 1 9
Figure 3. MVR-300 Components (Back)
Item Description of MVR-300 Components in Figure 2 and Figure 3
1 Coin slot to release bezel
2 Magnetic switch positions 1 (● on top) and 2 (●● on bottom)
3 Multi-color status LED
4 Grill
5 Decorative snap-on bezel
6 Cover plate (hinged)
7 Captive set screw
8 Detector base
9 Sensor type/calibration and ID/serial number labels
10 Mounting slots (x6)
11 Test point access holes (x2)
12 Sensor alignment ribs (x3)
13 Replaceable sensor module
14 Direction arrows (x2) for proper mounting
15 Hinges for cover plate
16 Hinges for bezel
17 Snap locks for bezel
18 Calibration adapter (fits cover plate and detector base)
19 Firmware version and part number/calibration labels
20 Configuration DIP switches (1-8)
21 Relay 1 output connectors (low gas alarm)
22 Relay 2 output connectors (high gas alarm or fault)
23 Power connectors
24 Modbus serial communications connectors
25 Rubber boot for Modbus port
26 Wiring harness
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SECTION 3. INSTALLATION
3.1 General Information for Installation
Every detail of installation location is critical to ensure overall system performance and effectiveness.
Strict compliance and considerable thought must be given to every detail of the installation process,
including, but not limited to the following:
•Regulations as well as local, state, and national codes that govern the installation of gas detection
equipment
•Electrical codes that govern the routing and connection of electrical power and signal cables to gas
detection equipment
•The full range of environmental conditions to which the detectors will be exposed (refer to section 6:
Sensor Principle on page 32 for more information on ambient conditions and cross-sensitivity)
•The physical characteristics of the gas or vapor to be detected
•The specifics of the application (e.g., possible leaks, air movement/draft, etc.)
•The degree of accessibility required for maintenance purposes
•The types of optional equipment and accessories that will be used with the system
•Any limiting factors or regulations that would affect system performance or installations
•Wiring details, including the following:
oWiring must be connected as indicated in this manual.
oThe wiring for power and relays must be selected and fused according to the rated voltages,
currents, and environmental conditions.
oIf stranded conductors are used, a ferrule should be used.
oA switch or circuit breaker must be included in the installation.
oThe switch or circuit breaker must be suitably located and easily reached.
oThe switch or circuit breaker must be marked as the disconnect device for the equipment.
3.2 Mechanical Installation
•The detector fits in most 2-gang electrical back boxes (not included) (See Section 10 for details on
the custom UK version of the MVR-300)
•The detector must be accessible for maintenance (e.g., adjustment)
•The access pathway of the refrigerant gas to the sensor must not be obstructed
•The detector should be installed about 4 to 6 inches (100 to 150 mm) above the floor level
Figure 4. A Sampling of 2-Gang Electrical Boxes Supported by the MVR-300
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MVR-300™ Refrigerant Gas Detector
P/N: 6203-9000 Version 1 11
Figure 5. Typical MVR-300 Installation in an Occupied Space Application
Figure 6. Recommended Installation Locations
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3.3 Configuration
Configuration is accomplished via switches or from a Remote Terminal Unit (RTU) on a Modbus serial
communications network. Review the default settings to determine if they are suitable for your particular
application. If default values are not suitable, change the configuration using the DIP switches, or via the
Modbus interface. A summary of switches is shown below. For details on Modbus communications
registers, refer to Section 8.9: Modbus Registers on page 36.
NOTICE
By default, switch configurations supersede Modbus configurations
. Use Modbus
register 2007 (Modbus Precedence over DIP Switch Setting
s) to change this
precedence.
Changes of configurations will not take effect until the detector is restarted (i.e., toggling switch 1 or
cycling power).
NOTICE
For a proper reset, switch 1 must be toggled (ON then OFF). If it is left ON, the detector
is held in reset mode and will not function correctly until the switch is returned to the
OFF position.
Figure 7. Switches for Configuring the MVR-300
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P/N: 6203-9000 Version 1 13
Switch Function Options and Descriptions Positions
1 Restart
Off = Normal Operation (default)
On = Restart MVR-300 (must return switch to OFF
position)
2, 3 Alarm ON
Delay
Off, Off = No delay (default)
Off, On = 5 minute delay
On, Off = 10 minute delay
On, On = 15 minute delay
4 Failsafe Relay
Selection
Off = Normal Relay Operation (default)
On = Failsafe Relay Operation
5 Relay 2 Fault
Indication
Off = High Alarm or Fault (default)
On = High Alarm Only
6 Alarm
Latching
Off = Alarms automatically reset (default)
On = Alarms latch and require manual reset
7 Buzzer
Disable
Off = Buzzer enabled (default)
On = Buzzer disabled
8
Reset
Detector
Settings to
Factory
Default Values
Off = Normal operation
On = Used in reset procedure for resetting Modbus
registers to their factory default values (see section
4.3.2 on page 21 for reset information and section 8.9
on page 36 for Modbus registers and default values).
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3.4 Electrical Installation
CAUTION
A switch or circuit breaker must be included in the installation. The switch or circuit
breaker must be suitably located and easily reached, and it must be marked as the
disconnect device for the equipment.
CAUTION
Ensure all wiring connections are made before applying power.
CAUTION
This product uses semiconductors which can be damaged by electrostatic discharge
(ESD). When handling the printed circuit boards (PCBs),
observe proper ESD
precautions so that the electronics are not damaged.
CAUTION
RS-485 signal cable must be insulated to the highest voltage level in the system. Protect
the RS-485 signal cable by using the supplied installation kit.
CAUTION
Wiring must be in compliance with national and local wiring codes.
NOTICE
When inserting wire into the terminal, release the spring clamp by pushing the release
latch back.
Step Description of Electrical Installation
1. Remove bezel by releasing the two snap locks. When installed, insert coin into the slot to
remove.
2. Remove cover plate by loosening the set screw.
3. Observing proper polarity, connect wires for power to the appropriate terminals.
Power Label Wiring
Termination
Figure 8. Wiring Power
100 to
240 VAC L VAC line
N VAC neutral
Earth
Ground G VAC earth
ground
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Step Description of Electrical Installation
4. Observing proper polarity, connect normally closed (NC) common (COM), and normally open
(NO) wires for relays to the appropriate terminals.
Figure 9. Wiring Relay 1 (Low Gas Alarm) and Relay 2 (High Gas Alarm or Fault)
5. Observing proper polarity, make the Modbus connections as follows, using the figures below
for reference.
Label Description
Figure 10. Modbus Wiring Terminals
A RS-485 “A” (non-inverted)
B RS-485 “B” (inverted)
G RS-485 shield
•Prepare signal cable and put boot over the signal cable ().
•Add ferules if required ().
•Apply 10 cm piece of shrink wrap as close to the wire ends/ferules as possible while
leaving some free wire to allow connection to the detector ().
•Heat the shrink wrap ().
•Connect signal wires/ferules to the detector ().
•Slide rubber boot along the wire and shrink wrap assembly and connect it to the
detector ().
Figure 11. Details for Connecting Modbus Communications Wiring
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Step Description of Electrical Installation
6. Confirm configuration of switches. Refer to Section 3.3 on page 12.
7. Place detector into electrical back box (not included) and secure through the appropriate
mounting slots.
Figure 12. Secure the MVR-300 and Wiring into the Back Box
8. Put cover plate back into hinge and tighten the set screw.
Figure 13. Replace and Secure Cover Plate
9. Put the bezel back into hinge and snap on.
Figure 14. Replace the Bezel
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SECTION 4. OPERATION
4.1 Start-up
Step Description
1. Switch power on.
2. Observe start-up sequence and warm-up phase.
•Green LED will blink at 0.5 Hz for about 5 minutes
•Modbus flag for warm-up is set
•Buzzer is off
•Relay state is “no alarm”
3. Observe normal operation.
•Green LED is steady on
•Buzzer is off
•Relay state is “no alarm”
4.2 Alarm Management Function and Configuration
The MVR-300 offers several different ways how the detector behaves in case of a refrigerant alarm. The
alarm manager can either be configured through the switches or the Modbus interface.
4.2.1 Default Alarm Function
If the refrigerant concentration raises above the alarm 1 set-point:
•The LED flashes red with 0.5 Hz
•The buzzer beeps at 0.5 Hz
•The alarm 1 relay changes state
•The Modbus alarm 1 flag is set.
Once the alarm 1 condition is no longer present and below the hysteresis value (imposed to avoid relay
chatter), the detector returns to normal operation.
If the refrigerant concentration raises above the alarm 2 set-point:
•The LED flashes red with 2 Hz.
•The buzzer beeps at 2 Hz
•The alarm 2 relay changes state
•The Modbus alarm 2 flag is set.
Once the alarm 2 condition is no longer present and below the hysteresis value (avoiding relay chatter),
the detector returns to alarm 1 state.
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18 P/N: 6203-9000 Version 1
Figure 15. Default Alarm Generation
4.2.2 Alarm Delay – Switches 2 and 3
To avoid premature alarms, ensuring the presence of refrigerant for a certain amount of time, the
triggering of the alarm can be delayed for a short period of time. Unless the alarm condition is present for
at least the delay time, the alarm will not be triggered.
Figure 16. Alarm ON Delay (Alarm Condition Must Be Present for at Least the Programmed Time)
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MVR-300™ Refrigerant Gas Detector
P/N: 6203-9000 Version 1 19
Figure 17. Alarm ON Delay (A Shorter Delay Time Is Disregarded)
Figure 18. Alarm ON Delay for Multiple Alarm Levels
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20 P/N: 6203-9000 Version 1
4.2.3 Failsafe – Switch 4
If ON, the relays will change state whenever either of the following occurs.
•Power loss
•Alarm condition.
4.2.4 Alarm 2 Relay – Switch 5
If ON, the relay will only change state as a result of an alarm condition. In the default configuration,
Relay 2 will also indicate critical faults.
4.2.5 Latching Alarm State – Switch 6
If ON, the relay and Modbus flag will not change state until the concentration is below the alarm level and
it is acknowledged. The acknowledgement can either happen by tapping and holding the magnetic wand
for 5 seconds to the switch indicated as (●●) or by changing the respective Modbus flag to 0.
In the default configuration the alarms will automatically reset when the gas level is below the alarm
thresholds.
Figure 19. Latched Alarm Requiring Acknowledgement and Gas Concentration below Alarm Level
4.2.6 Buzzer Disable – Switch 7
If ON, the buzzer is disabled and will not sound.
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