1: OPERATING AREA AND CONDITIONS
The Bacharach MGS-550 is an instrument for the
continuous monitoring of toxic and combustible gases,
oxygen and refrigerants in ambient air. The instrument
is housed in a rugged ABS or aluminum enclosure for
indoor and outdoor applications. The instrument can
be connected to a Bacharach monitoring system or a
Programmable Logic Controller (PLC). With the inte-
grated alarm relay configuration, 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, perma-
nent locations.
The instrument is powered by 19.5 to 28.5 VDC or
24 VAC (± 20%). The measured gas concentration is
converted to a 4 to 20 mA, 0 to 5 V, 0 to 10 V, 1 to 5 V,
2 to 10 V analog and digital Modbus RTU output
signal. The instrument accepts wire sizes of 16 to
24 AWG (0.2 to 1.5 mm
2
).
P/N: 1100-0999
Revision 0
June 5, 2015
2: SAFETY INSTRUCTIONS
USER MANUAL: Before using this equipment, carefully read
and strictly follow the User Manual (part number
1100-1000). The user must fully understand and strictly
observe the instructions. Use the equipment only for the
purposes listed and under the conditions specified in that
document.
CODE COMPLIANCE: Comply with all local and national
laws, rules and regulations associated with this equipment.
GENUINE PARTS: Use only genuine Bacharach spare parts
and accessories, otherwise proper functioning of the equip-
ment may be impaired.
FLAME PROOF AND EXPLOSION PROOF JOINTS: Joints of
the flame proof/explosion proof enclosure are not in accor-
dance with the relevant minimum or maximum values of
EN/IEC 60079-1. The joints are not intended to be re-worked
by the user.
EXPLOSIVE DIRECTIVES: As long as no EC-Type Examination
Certificate per Annex II, clauses 1.5.5, 1.5.6 and 1.5.7 of
Directive 94/9/EC exists: the measuring function of the gas
detection transmitter for explosion protection, according to
Annex II, clauses 1.5.5, 1.5.6 and 1.5.7 of Directive 94/9/EC
is not covered.
When using the product in areas subject to explosion
hazards, refer to the following:
● Instruments or components for use in explo-
sion-hazard areas which have been tested and
approved according to national, European or
international Explosion Protection Regulations
may only be used under the conditions specified
in the approval and with consideration of the
relevant legal regulations.
● The instruments or components may not be
modified in any manner. The use of faulty or
incomplete parts is forbidden. The appropriate
regulations must be observed at all times when
carrying out repairs on these instruments or
WARNING: Strictly follow the
instructions in the User Manual
(part number 1100-1000).
CAUTION: DO NOT USE the MGS-550
in oxygen-enriched environments of
>21% oxygen. High “off-scale” read-
ings may indicate an explosive con-
centration.
3: MOUNTING
ENVIRONMENTAL CONSIDERATIONS: Carefully consider the
full range of environmental conditions to which the instru-
ments will be exposed.
TARGET GAS CONSIDERATIONS: The physical data of the gas
or vapor to be detected must be observed.
APPLICATION CONSIDERATIONS: The specifics of the appli-
cation (for example, possible leaks, air movement/draft, etc.)
must be observed.
ACCESSIBILITY CONSIDERATIONS: The degree of accessibili-
ty required for maintenance purposes must be granted.
ACCESSORY CONSIDERATIONS: The types of optional and
accessory equipment that will be used with the system must
be kept in mind.
SENSOR POSITIONING: When installing the instrument or
the remote sensor, the sensor opening should always be
pointing downward.
SUN SHIELD CONSIDERATIONS: If the instrument is exposed
to direct sunlight, the use of a sunshield is recommended.
4: WEIGHTS AND DIMENSIONS (APPROXIMATE)
FULL-SIZE
MOUNTING
TEMPLATES --
DO NOT
RESCALE
115.0 mm (4.53 in)
120.6 mm (4.75 in)
Mounting
Point (ABS)
Mounting
Point (ABS)
Mounting
Point
(Ex d)
Mounting
Point (Ex d)
144.1 mm (5.67 in)
IP66-Rated ABS Enclosure
with Local
Sensor
Flame
Proof/
Explosion
Proof Ex d
Enclosure
with Local
Sensor
Magnetic
Wand
COMPONENT
WIDTH
HEIGHT
DEPTH
mm
in
mm
in
mm
in
General Purpose Enclosure
Explosion Proof Encosure
210
125
8.3
4.9
225
190
8.9
7.5
85
90
3.4
3.5
kg
lbs
1
1.6
2
3.5
WEIGHT
