MSA MGS-550 User manual

Operating Manual
MGS-550
Fixed Gas Detector
Order No.: H1100-1000/01
Print Spec: 10000005389 (R)
CR: 800000058146
MSAsafety.com
US

© MSA 2022. All rights reserved
WARNING!
These instructions must be provided to users before use of the product and retained for ready reference by the user. Read
this manual carefully before using or maintaining the device. The device will perform as designed only if it is used and
maintained in accordance with the manufacturer's instructions. Otherwise, it could fail to perform as designed, and persons
who rely on this device could sustain serious injury or death.
The warranties made by MSA with respect to the product are voided if the product is not installed and used in accordance
with the instructions in this manual. Please protect yourself and your employees by following the instructions.
Please read and observe the WARNINGS and CAUTIONS inside. For additional information relative to use or repair, call
1-800-MSA-2222 during regular working hours.
For countries of Russian Federation, Republic of Kazakhstan and Republic of Belarus, the gas detector will be delivered
with a passport document that includes valid approval information. On the CD with manual instruction attached to the gas
detector the user will find the documents "Type Description" and "Test Method" - appendixes to Pattern Approval Certificate
of Measuring instrument, valid in the countries of use.
MSA is a registered trademark of MSA Technology, LLC in the US, Europe and other Countries. For all other trademarks
visit https://us.msasafety.com/Trademarks.
1000 Cranberry Woods Drive
Cranberry Township, PA 16066
USA
Phone: 1-800-MSA-2222
Fax: [phone]
For your local MSA contacts, please go to our website www.MSAsafety.com

US MGS-550 3
WARRANTY POLICY
MSA Bacharach warrants this instrument, excluding sensors, to be free from defects in materials and workmanship for a period of two
years from the date of purchase by the original owner. The sensors have a pro-rated warranty period of 6 to 18 months, depending on
the sensor type. 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 instrument has not been used and maintained per the instructions in this manual or has been
abused, damaged, or modified in any way. This instrument 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. Contact the manufacturer for a number and procedures required for product transport.
SERVICE POLICY
MSA Bacharach maintains an instrument service facility at the factory. Some MSA Bacharach distributors/agents may also have repair
facilities; however, MSA Bacharach assumes no liability for service performed by anyone other than MSA Bacharach personnel.
Repairs are warranted for 90 days after date of shipment (sensors, pumps, filters and batteries have individual warranties). Should your
instrument require non-warranty repair, you may contact the distributor from whom it was purchased or you may contact MSA
Bacharach directly.
If MSA Bacharach is to do the repair work, send the instrument, prepaid, to the closest Service Center.
Service Location Service Contact Information Service Shipping Address
United States
http://mybacharach.com/rmaform/
Phone: [phone]
Toll Free: 1 800 736 4666
Fax: [phone]
Email: [email protected]
MSABacharach
621 Hunt Valley Circle
New Kensington, PA 15068, USA
ATTN: Service Department
Canada Phone: [phone]
Email: [email protected]
MSAEdmonton Repair Service
12130 – 154th Street
Edmonton, Alberta
T5V 1J2
Always include your RMA #, address, telephone number, contact name, shipping/billing information and a description of the defect as
you perceive it. You will be contacted with a cost estimate for expected repairs prior to the performance of any service work. For liability
reasons, MSA Bacharach has a policy of performing all needed repairs to restore the instrument to full operating condition.
Prior to shipping equipment to MSA Bacharach, contact our office for an RMA # (returned merchandise authorization). All returned
goods must be accompanied with an RMA number.
Pack the equipment well (in its original packing if possible), as MSA Bacharach cannot be held responsible for any damage incurred
during shipping to our facility.
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 MSA Bacharach, Inc.
All software utilized and/or distributed by MSA 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 MSA 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.

4 MGS-550 US
Contents
1 Safety 5
1.1 General Safety Statements 5
1.2 Safe Connection of Electrical Devices 5
2 Description 5
2.1 Product Overview 5
2.2 Key Product Features 6
2.3 General Overview 7
2.4 Sensor Styles 8
3 Installation 8
3.1 General Information for Installation 8
3.2 Installation Restrictions 9
3.3 Mechanical Installation 9
3.4 Electrical Installation 9
4 Operation 15
4.1 Overview of Normal Operation 15
4.2 Menus 19
4.3 Functions 22
4.4 Parameters 25
5 Maintenance 31
5.1 Maintenance Intervals 31
5.2 Making Adjustments to Sensors 31
5.3 Troubleshooting 34
5.4 Sensor Maintenance 39
5.5 Replacing the Instrument Electronics 44
5.6 Replacing the Interface Board 45
5.7 Cleaning the Instrument 45
6 Factory Default Settings 46
7 Sensor Principle 47
7.1 Electrochemical Sensors 47
7.2 Catalytic Bead Sensors 47
7.3 Semiconductor Sensors 48
7.4 Infrared Sensors 48
8 Disposing of the Instrument 48
8.1 Disposing of Electrical and Electronic Equipment 48
8.2 Disposing of Electrochemical Sensors 49
9 Technical Data 49
9.1 General Specifications 49
9.2 Sensor Specifications 50
9.3 Modbus Registers 51
10 Ordering Information 57
10.1 MGS-550 Instrument Only 57
10.2 MGS-550 Gas Detector, IP66 with IP66 Sensor 57
10.3 MGS-550 5m Remote and Second Sensing Heads 59
10.4 MGS-550 Replacement Parts and Accessories 60

1 Safety
US MGS-550 5
1 Safety
1.1 General Safety Statements
WARNING!
lBefore using this product, carefully read and strictly follow the instructions in the manual.
lUse the product only for the purposes specified in this document and under the conditions listed.
lEnsure that product documentation is retained, made available, and appropriately used by anyone operating the
product.
lComply with all local and national laws, rules, and regulations associated with this product.
lOnly trained and competent personnel may use this product.
lOnly 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 MSA Bacharach or personnel qualified by
MSA Bacharach.
lUse only genuine MSA Bacharach spare parts and accessories. Otherwise, operation may be impaired.
lOnly operate the product within the framework of a risk-based alarm signaling concept.
Failure to follow these warnings can result in serious personal injury or death.
1.2 Safe Connection of Electrical Devices
WARNING!
Before connecting this instrument to electrical devices not mentioned in this manual, consult the manufacturer or a
qualified professional.
Failure to follow this warning can result in serious personal injury or death.
2 Description
2.1 Product Overview
The MSA Bacharach MGS-550 continuously monitors indoor or outdoor ambient air for the following gases:
ltoxic and combustible gases
loxygen
lrefrigerants.
The instrument is housed in a rugged ABS enclosure (general purpose or “GP” housing).
The instrument can be connected to a MSA Bacharach MGS-408 controller or a Programmable Logic Controller (PLC).
With the integrated alarm relays, the instrument can be operated as a stand-alone unit (with additional local alarm
signaling). The instrument is designed to be installed in non-classified, non-hazardous, permanent locations.

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2 Description
WARNING!
lDanger of explosions. This product is neither certified nor approved to be operated in oxygen-enriched
atmospheres.
lThe device is NOT intended to be used in areas classified as hazardous.
Failure to follow these warnings can result in serious personal injury or death.
2.2 Key Product Features
lEnclosure options—General-purpose (GP): ABS plastic housing (rectangular)
lPower options (refer to section 9.1 General Specifications):
o24 VAC
o19.5 to 28.5 VDC
lMulti-function, 5-digit LED display
ogas concentrations
ostatus messages
omenu choices
lDiagnostic/status LEDs (3)
lDigital output Modbus RTU signal
lIndependently configurable analog outputs (2) (based on measured gas concentration)
oAnalog output 4 to 20 mA
oAnalog output 0 to 5 V
oAnalog output 0 to 10 V
oAnalog output 1 to 5 V
oAnalog output 2 to 10 V
lRedundant sensor mapping option (one sensor can be mapped to both analog outputs)
lMenu navigation options:
oTactile switches on the front cover
oNon-intrusive magnetic wand on the front cover
lNon-intrusive magnetic wand can be used to configure, calibrate, and maintain the device

2 Description
US MGS-550 7
2.3 General Overview

8 MGS-550 US
3 Installation
2.4 Sensor Styles
Local Sensor 5 m (16 ft) Remote Sensor
3 Installation
3.1 General Information for Installation
Every detail of installation site selection 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:
lRegulations as well as local, state, and national codes that govern the installation of gas monitoring equipment
lElectrical codes that govern the routing and connection of electrical power and signal cables to gas monitoring
equipment
lThe full range of environmental conditions to which the instruments will be exposed
lThe physical characteristics of the gas or vapor to be detected
lThe specifics of the application (e.g., possible leaks, air movement/draft, etc.)
lThe degree of accessibility required for maintenance purposes
lThe types of optional equipment and accessories that will be used with the system
lAny limiting factors or regulations that would affect system performance or installations
lWiring details, including the following:
oThe general purpose enclosure provides six M16 entry points, which can be used for field wiring, direct
attachment of a sensor, or wiring of a remote sensor.
oUnused openings must be closed with a suitable plug and gasket, maintaining the IP rating.
oSecondary circuit must be supplied from an isolating source (not applicable for relay circuits).
oThe wiring for the 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.
oTo improve RFI immunity in extreme environments, it might be necessary to ground the shield of the
communications cable at the PLC, front-end controller, or Building Management System (e.g., the chassis,
the ground bus-bar, etc.).

3 Installation
US MGS-550 9
3.2 Installation Restrictions
The installation location must have appropriate supply power available for the instrument (i.e., 19.5 to 28.5 VDC or 24
VAC). Refer to Section 9 Technical Data. This ultimately determines the distance the instrument can be mounted from
the controller or power supply.
WARNING!
The MGS-550 must be powered by either:
la suitable UL/CSA/IEC 60950 certified power supply that is isolated from line voltage by double insulation, or
lan appropriately rated UL listed/CSA/IEC Class 2 transformer.
Failure to follow this warning can result in serious personal injury or death.
lThe instrument accepts wire sizes of 16 AWG (1.5 mm2) to 20 AWG (0.5 mm2).
lDepending on the configuration, use at least a shielded, multi-conductor cable.
lThe instrument must not be exposed to radiant heat that will cause the temperature to rise beyond the limits
stated in Section 9 Technical Data. The use of a reflecting shield is recommended.
lThe enclosure is weatherproof within environmental specifications and suitable for outdoor installation.
lEach instrument must be installed and operated in an environment that conforms to the specifications listed in
Section 9 Technical Data.
3.3 Mechanical Installation
lSelect a mounting location that is accessible for maintenance and adjustment.
lEnsure that any targeted gas or vapor has unobstructed access to the sensor.
lConsider implications of the future use of accessories and maintenance equipment.
lEnsure that the mounting surface is flat and plumb.
lEnsure that any installed sensor is pointing downwards.
lMSA Bacharach recommends using M5 bolts (or smaller) with hex socket caps to mount the device.
3.4 Electrical Installation
3.4.1 Preparations
WARNING!
• Ensure wiring for relays and connections for sensor(s) are made before applying power.
• 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.
Failure to follow these warnings can result in serious personal injury or death.
NOTE: For unused 4 to 20 mA analog outputs, ensure that a jumper (pin 3 to 4 and pin 5 to 6) is installed. Otherwise, a
fault may be displayed if the wiring does not match the configuration. The analog outputs are designed as sources.

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3 Installation
• Open the enclosure lid. Loosen six (6) screws using
an M5 hex key and remove the lid from the base.
• Disconnect the ribbon cable from the processor
board on the lid. Set the lid aside and continue to
wiring procedure.
3.4.2 Power and Signal Wiring
lUsing appropriate cable glands and/or conduit, connect the wires for power and signal to the appropriate terminal
as indicated in the figure and wiring table that follow.
lPolarity must not be reversed.
lFor 24 VAC installations in a daisy-chain configuration, the neutral polarity must be maintained for all instruments.
lFasten terminal screws.

3 Installation
US MGS-550 11
Connection Description Pin Label Wiring Termination
Power
24 VAC 1 +24 VDC/AC 24 VAC line
2 PWR GND 24 VAC neutral
24 VDC 1 +24 VDC/AC 24 VDC positive
2 PWR GND 24 VDC ground
Analog Output
Analog Output 1*
3 ANALOG 1 GND Analog output 1 ground
4 ANALOG OUT 1 Analog output 1 signal
(+)
Analog Output 2*
5 ANALOG 2 GND Analog output 2 ground
6 ANALOG OUT 2 Analog output 2 signal
(+)
Digital Output Modbus Network
Communications
7 RS-485 GND RS-485 shield
8 A RS-485 “A” (non-
inverted)
9 B RS-485 “B” (inverted)
* For 3-wire, single-sensor DC installations: connect pins 1 and 2 of 24 VDC, and connect pin 4 to the analog input of
the control system. For 4-wire, dual-sensor DC installations: connect pins 1 and 2 of 24 VDC, connect pin 4 to one
analog input of the control system, and connect pin 5 to another input of the control system.
lIf central monitoring or a PLC is used, connect the signal cable shielding at the controller only.
lIf an analog output is unused and configured as a 4 to 20 mA output, then the corresponding output connectors
must be shorted or jumpered, otherwise a fault will occur. For unused analog output 1 configured as 4 to 20 mA
output, wire pin 3 to pin 4. For unused analog output 2 configured as a 4 to 20 mA output, wire pin 5 to pin 6.
These jumper wires are installed at the factory, but should be removed for voltage outputs or if connections are
made to the analog outputs.
3.4.3 Relay Wiring
WARNING!
At voltages > 30 VAC or > 42.2 VDC, the relay cables must be enclosed in protective conduit, or double-insulated
cables must be used.
Failure to follow this warning can result in serious personal injury or death.

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3 Installation
lUsing appropriate cable glands and/or conduit, connect the wires for relay 1, relay 2, and relay 3 to the terminals
(see previous wiring figure) as indicated in the following wiring table. (Note that any one of 6 alarms or 3 fault
types may be mapped to any relay.)
Function Pin Label Wiring Termination
Relay 1 Output
10 RELAY 1 NC Relay 1 NC contact
11 RELAY 1 C Relay 1 common contact
12 RELAY 1 NO Relay 1 NO contact
Relay 2 Output
13 RELAY 2 NC Relay 2 NC contact
14 RELAY 2 C Relay 2 common contact
15 RELAY 2 NO Relay 2 NO contact
Relay 3 Output
16 RELAY 3 NC Relay 3 NC contact
17 RELAY 3 C Relay 3 common contact
18 RELAY 3 NO Relay 3 NO contact
To change relay designations, see section 4.4.2 Relay Designation (RX-xx). For default values, see section6 Factory
Default Settings.
When configured according to the factory default settings, the relays are de-energized during normal operation (not
failsafe). Fail-safe mode can be configured and relay operation is opposite of the wiring table. See section 4.4.2 Relay
Designation (RX-xx). The terminal designators in the wiring table show factory defaults in normal operation (not
failsafe) mode with the relays de-energized.
NOTE: To ensure that a fault is easily “recognized” (that is, without needing to look directly at the instrument’s display),
one relay should be designated for instrument faults and an alarm device should be connected to the fault relay.
3.4.4 Install Remote Sensing Head
lRemove a blind-plug from the enclosure (if applicable).
lFeed the connector of the sensor (see below, left) through a cable gland or conduit (if applicable), through the
opening of the enclosure, and then into the enclosure.
lSecure the cable gland (with attached gasket) or appropriate conduit into the housing in order to maintain IP
rating.
lPlug the sensor connector into the socket until the lock engages. For a new instrument with no sensor connected,
it does not matter which socket is used first. However, if a sensor is already connected, then it should be left
plugged into its socket.
lIf two remote sensors are to be installed, register only one sensor at a time. Refer to section 4.3.6 Register
Sensor (F-06).

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NOTE: Sensors are not automatically recognized and must but individually registered using function F-06. See section
4.3.6 Register Sensor (F-06), section4.3.7 De-register One Sensor (F-07), and section 4.3.8 De-register All Sensors
and Reset Node Address (F-08).
3.4.5 Connecting One or More MGS-550s to an MSA Bacharach Controller
NOTE: For wiring and configuration information, please refer to the manual which was included with the MSA
Bacharach controller (e.g., MGS, etc.).
lAt the central control system, connect the shield of the wires to the earth ground of the controller (e.g., the
chassis, the ground bus-bar, etc.).
lFor 24 VDC installations, the input is protected. If the polarity is reversed, the instrument will not power-up.
lFor 24 VAC installations in daisy-chain, the neutral polarity must be maintained for all instruments (see example
below).

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3 Installation
3.4.6 Modbus RTU Interface
lFor the Modbus network use an 18 to 24 AWG (0.5 to 1 mm2) shielded twisted pair wire with a 120Ω
characteristic impedance.
lThe Modbus address, baud rate, stop bit, parity and slave termination is configured through the setup menu. No
jumpers or hardware switch settings are required.
lEnsure that the communication parameters within the network, including the Building Management System, are
configured identically. See section 4.4.5 Modbus Configuration (MB-xx).
lIf the MGS-550 is at the end of the Modbus network, the terminating resistor must be set to “IN”. All other
instrument terminating resistor must be set to “OUT” (factory default). See section 4.4.5 Modbus Configuration
(MB-xx).
3.4.7 Conclusion
After all wiring is completed, connect the ribbon cable, replace the lid, and tighten the six (6) screws with an M5 hex key.
NOTICE
DO NOT allow the lid / sensor to hang from the ribbon cable. Failure to follow this notice may result in damage to the
product.

4 Operation
US MGS-550 15
4 Operation
4.1 Overview of Normal Operation
WARNING!
Before leaving the instrument for normal operation, check the configuration for proper settings and check calibration.
Failure to follow this warning can result in serious personal injury or death.
4.1.1 Applying Power and the Start-up Sequence
After applying power, the instrument will go through a start-up sequence (LED test, software version, and initialization)
and start the warm-up period. The power LED will blink and, by default, the display will remain blank. To enable the
display of gas type and concentration, use parameter P1-01 which will cause the display to toggle between the target
gas name and a value of “0” for the sensor in warm-up. See section 4.4.6 Display Mode (P1-01).
The instrument output will be OFFLINE (see section 4.3.1 Offline Mode (F-01)). If two sensors are installed, both target
gas names and “0”s will be toggled sequentially.
NOTE: Sensor warm-up times may be different for dual sensor configurations. The power LED will continue to blink as
long as at least one sensor is in warm-up.

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4 Operation
After the warm-up period, the instrument begins normal operation. The display toggles between the current gas
concentration and target gas name.
During normal operation, the left green LED is lit solid. Depending on the unit of measurement, the green LED for ppm
or %LEL is lit. If both of these LED are off, the unit of measurement is Vol%.
All configurations must be checked at least initially, and the calibration must be checked initially and as needed.
4.1.2 Verifying Analog Signals
During normal operation the current output of the instrument is proportional to the detected gas concentration and can
be selected from the following.
l4 to 20 mA
l0 to 5 V
l1 to 5 V
l0 to 10V
l2 to 10 V
The MGS-550 uses different current values to indicate various modes of operation. See section 9.1 General
Specifications for additional information.
4.1.3 Verifying the Digital Modbus Signal
The MGS-550 provides a Modbus RTU digital interface. All status messages and most parameters which can be
accessed and/or configured through the menu can also be accessed and/or configured via a Building Management
using a Modbus network. See section 4.4.5 Modbus Configuration (MB-xx).
4.1.4 The 5-Digit Display and LEDs
In normal operation, the 5-digit, 7-segment LED display toggles between the gas name (CO2 in this example, and the
measured gas concentration (291 ppm in this example).
In addition, the following special symbols and unique messages may also be displayed during operation of the
instrument.

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US MGS-550 17
Symbol/Message Description
The measuring range of the sensor has been exceeded (“upper hockey sticks”
symbol).
The sensor drifted negative (<0) (“lower hockey sticks” symbol).
If a fault has been detected, the display toggles between gas name and "Exxx",
and the green power LED is off. "E100" indicates a critical fault and "E300"
indicates a non-critical fault. A non-critical fault does not need immediate
attention, but should be mitigated at the next scheduled maintenance (see
section 5 Maintenance). If a relay has been designated to the critical fault, it is
asserted. E400 is a configuration warning that happens after a second sensor is
added to warn the user that the sensor is not driving any relays or analog
outputs.
When the first alarm has been triggered, the display will toggle between gas
name, "A1" and current gas concentration. If a relay has been designated to the
first alarm, it is asserted.
When the second alarm has been triggered the display will toggle between gas
name, "A2" and current gas concentration. If a relay has been designated to the
second alarm, it is asserted.
When the third alarm has been triggered the display will toggle between gas
name, "A3" and current gas concentration. If a relay has been designated to the
third alarm, it is asserted.
The instrument is offline. See section 4.3.1 Offline Mode (F-01).
The first character represents an “M”. This is found in the Modbus parameters
(MB-xx). Refer to section 4.4.5 Modbus Configuration (MB-xx).
This is a confirmation that is displayed before a sensor is registered. Tap
[ENTER] to confirm registration of sensor 1 or registration of sensor 2. For more
information, refer to section 4.3.6 Register Sensor (F-06).
This message is shown after successful completion of a functional operation of
one of the sensors (for example, after registering a sensor, after calibrating a
sensor, etc.).
This is a confirmation display prior to de-registering all sensors and resetting
node addresses (F-08). Tap [ENTER] to confirm reset. See section 4.3.8 De-
register All Sensors and Reset Node Address (F-08) for additional information.

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4 Operation
Symbol/Message Description
This is a second confirmation display prior to de-registering all sensors and
resetting node addresses (F-08). Tap [ENTER] to confirm reset. section 4.3.8
De-register All Sensors and Reset Node Address (F-08) for additional
information.
The unit of measurement is indicated by two green LEDs on the right side (upper LED for ppm, lower LED for %LEL,
both LEDs off for Vol%). The green LED on the left indicates that the instrument is in normal operation.
NOTE: If two sensors are installed for the same gas, but have different measuring ranges, the unique sensor identifier
or UID (see label on the sensor) will be displayed in addition to the gas name.
NOTE: Depending on the sensor and measuring range, the gas concentration may or may not be shown with a decimal
point.

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US MGS-550 19
4.2 Menus
4.2.1 General Navigation
The MGS-550 offers two methods of navigating through the menu.
• Use the non-intrusive magnetic wand (tapping above
the “magnetic” icons with dashes)
• Use the internal push buttons (pressing the
push button points).
Magnetic Switch
Points
Internal Push
Button Points
Function(s)
Tapping/pressing and holding the [i] key for more than 3 seconds gives
access to the user menu (which displays the firmware version first). It is
also used to return to the next higher menu item without saving any
changes (“escape”). A short tap/press (< 3 seconds) of the [i] key also
brings up a sensor identification on the display, toggling between the serial
number (UID) of Sensor 1 and Sensor 2.
Tapping/pressing the magnetic wand over the [UP] / [DOWN] keys scrolls
through the menu selections. Holding the magnetic wand at the key is
interpreted as repeat tapping with an eventual acceleration. When the last
menu item is reached, the menu will roll over to the first menu item in the
list. A diagnostic scan can be entered from normal operation by tapping
and holding [UP] for more than 3 seconds.
Tapping/pressing the [ENTER] key (↵) confirms a selection. In normal
operation tapping/pressing and holding the [ENTER] key for more than 3
seconds will cancel the OFFLINE mode, or release any latched alarm, or
acknowledge any acknowledgeable alarm, with priority given to OFFLINE
mode.
NOTE: The instrument is designed for the magnetic wand to be used with the enclosure lid in place. If the enclosure lid
is not in place, the magnetic wand may activate two or more keys at once due to cross-talk.
NOTE: After 3 minutes of inactivity within a menu, the instrument times-out and returns to normal operation. When
changing a parameter, 3 minutes of inactivity will cause the instrument to time out and return to normal operation
without accepting any changes.
4.2.2 Checking Status and Changing Parameter Values
Select the menu item to be accessed by tapping [UP] / [DOWN].

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4 Operation
lWhen the desired menu item is displayed, tap [ENTER]. The current value or status will flash to indicate the user
interface has switched to data entry mode.
l[UP] / [DOWN] adjust the value of a numerical parameter or scroll through preset choices.
lOnce the display shows the intended value or choice, tap [ENTER] to validate the new parameter and return to
the previous menu.
4.2.3 Exiting the Menu
To get back into measurement mode, tap and hold the [i] key for more than 3 seconds. This will step back through the
menus and eventually return to normal operation.
4.2.4 Menu Overview
The menu is divided in functions and parameters. Individual parameters are grouped into logical menus.
Function Description
F-01 00 = instrument online, 01 = instrument OFFLINE
F-02 1 = zero sensor 1, 2 = zero sensor 2
F-03 1 = span sensor 1, 2 = span sensor 2
F-04 Instrument test
F-05
Access parameters:
Parameters Description
S1-XX Sensor 1 settings
S2-XX Sensor 2 settings – if connected
RX-XX Relay settings
AF-XX Alarm functions
AX-XX Analog output configuration
MB-XX Modbus configuration
P1-01 Display mode
B1-XX Buzzer settings
F-06 Register sensor
F-07 De-register one sensor
F-08 De-register all sensors and reset node address
F-09 Access diagnostics, system information, and fault parameters
F-10 Reset system to factory default setting
An example of the layered structure of functions, menus, and parameters is illustrated below. Individual functions and
parameters are described in detail in the sections that follow.