Bacharach GDC-350 User manual

Instruction 5909-9000
Operation Manual
Rev. 1 - January 2012
Product Leadership xTraining xService xReliability

GDC-350 Operation Manual
ii 5909-9000 Rev 1
DISCLAIMER
Under no circumstances will Bacharach, Inc. be liable for any claims, losses, or
damages resulting from or arising out of the repair or modification of this equipment
by a party other than Bacharach service technicians, or by operation or use of the
equipment other than in accordance with the printed instructions contained within this
manual or if the equipment has been improperly maintained or subjected to neglect or
accident. Any of the forgoing will void the warranty.
REVISIONS
Bacharach, Inc. makes no warranty or representation, expressed or implied including
any warranty of merchantability or fitness for purpose, with respect to this manual. All
information contained in this manual is believed to be true and accurate at the time of
printing. However, Bacharach reserves the right to make changes at any time without
notice. Revised copies of this manual can be obtained by contacting Bacharach, Inc.
Should you detect any errors or omissions in this manual, please contact the
company at the following address.
Bacharach, Inc.
621 Hunt Valley Circle
New Kensington, PA 15068-7074
USA
Toll free: 1-800-736-4666
Fax: [phone]
E-mail: [e-mail]
Website: www.MyBacharach.com
In no event will Bacharach, Inc., or its officers or employees be liable for any direct,
special, incidental, or consequential damages resulting from any defect in any
manual, even if advised of the possibility of such damages.
© 2012 Bacharach, Inc.

GDC-350 Operation Manual
5909-9000 Rev 1 iii
IMPORTANT
READ AND UNDERSTAND THIS MANUAL PRIOR TO USING THIS INSTRUMENT.
THIS INSTRUMENT SHOULD BE INSPECTED AND CALIBRATED AT REGULAR
INTERVALS BY QUALIFIED AND TRAINED PERSONNEL. FOR MORE
INFORMATION REFER TO THE “SYSTEM MAINTENANCE” AND “CALIBRATION
PROCEDURE” SECTIONS OF THIS MANUAL.
THIS INSTRUMENT HAS NOT BEEN DESIGNED TO BE INTRINSICALLY SAFE IN
HAZARDOUS OR EXPLOSION-RATED ENVIRONMENTS. FOR YOUR SAFETY,
DO NOT USE IT IN AREAS CLASSIFIED AS HAZARDOUS AREAS (E.G.,
EXPLOSION-RATED ENVIRONMENTS).
PURCHASE DATE:
PURCHASED FROM:
WARNINGS
CAUTION: More than one live circuit is associated with this device.
CAUTION: Disconnect power before servicing.
Supply voltage is 24 V (nominal) DC or AC (50/60 Hz).
This product is certified for electrical shock and electrical fire hazard only.
WARRANTY POLICY
BACHARACH, INC. WARRANTS THIS INSTRUMENT TO BE FREE FROM
DEFECTS IN MATERIALS AND WORKMANSHIP FOR A PERIOD OF TWO (2)
YEARS FROM THE DATE OF PURCHASE. INDIVIDUAL SENSOR ELEMENTS
HAVE DIFFERENT WARRANTIES, CHECK WITH FACTORY FOR SPECIFIC
SENSOR WARRANTY. THE WARRANTY STATUS MAY BE AFFECTED IF THE
INSTRUMENT HAS NOT BEEN MAINTAINED AND CALIBRATED AS PER THE
INSTRUCTIONS INDICATED IN THIS MANUAL OR HAS BEEN ABUSED OR
DAMAGED IN ANY WAY. THIS INSTRUMENT IS ONLY TO BE USED FOR
PURPOSES STATED HEREIN.

GDC-350 Operation Manual
iv 5909-9000 Rev 1
SERVICE POLICY
BACHARACH, INC. MAINTAINS AN INSTRUMENT SERVICE FACILITY AT THE
FACTORY. SOME BACHARACH DISTRIBUTORS / AGENTS MAY ALSO HAVE
REPAIR FACILITIES, HOWEVER, BACHARACH ASSUMES NO LIABILITY FOR
SERVICE PERFORMED BY ANYONE OTHER THAN 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 BACHARACH DIRECTLY.
IF BACHARACH IS TO DO THE REPAIR WORK, SEND THE INSTRUMENT,
PREPAID, TO BACHARACH, INC. AT THE FOLLOWING ADDRESS.
BACHARACH, INC.
621 HUNT VALLEY CIRCLE
NEW KENSINGTON, PA 15068
ATTENTION: SERVICE DEPARTMENT
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, BACHARACH HAS A POLICY OF
PERFORMING ALL NEEDED REPAIRS TO RESTORE THE INSTRUMENT TO
FULL OPERATING CONDITION.
PRIOR TO SHIPPING EQUIPMENT TO 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
BACHARACH CANNOT BE HELD RESPONSIBLE FOR ANY DAMAGE INCURRED
DURING SHIPPING TO OUR FACILITY.
NOTICES
COPYRIGHTS: 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.

GDC-350 Operation Manual
5909-9000 Rev 1 v
TABLE OF CONTENTS
1. OVERVIEW................................................................................................................ 1
1.1. General Description ............................................................................................ 1
1.2. Key Exterior Components ................................................................................... 1
1.3. Key Interior Components .................................................................................... 2
1.4. Sensor Aging and Calibration Extending Firmware (CEF)................................... 3
2. SPECIFICATIONS ..................................................................................................... 3
2.1. Controller Specifications ..................................................................................... 3
2.2. Sensor Specifications ......................................................................................... 5
2.3. Model Designations ............................................................................................ 6
3. INSTALLATION ......................................................................................................... 8
3.1. Sensor Mounting Heights.................................................................................... 8
3.2. Basic Enclosure.................................................................................................. 8
3.3. Remote Sensor Housing for Solid-State Sensors................................................ 9
3.4. Detailed Wiring Connections (Types A, B, and D)............................................... 9
3.5. Detailed Wiring Connections (Type E) ...............................................................10
3.6. Wiring the GDC-350 for Power ..........................................................................10
3.7. Wiring Remote Sensors (Voltage and Signal) ....................................................12
3.8. Wiring Relay Connections..................................................................................12
3.9. Installation Example 1: Type “A” with Enclosed Transformer..............................13
3.10. Installation Example 2: Type “B” with Remote Solid-State Sensor....................14
3.11. Installation Example 3: Type “D” with On-Board and Remote Sensors.............15
3.12. Installation Example 4: Type “E” with Two On-Board Sensors .........................16
3.13. Powering On the GDC-350 ..............................................................................16
4. CONFIGURATION AND OPERATION..................................................................... 16
4.1. General..............................................................................................................16
4.2. Test Functions ...................................................................................................17
4.3. DIP Switch Settings ...........................................................................................18
4.4. System Jumpers................................................................................................19
4.5. Adjusting Alarm Setpoints..................................................................................21
4.6. Relay Time Delays.............................................................................................23
4.7. Temperature Display – Unit of Measure.............................................................25
4.8. Latching Relay Function ....................................................................................25
4.9. LED Digital Display ............................................................................................26
5. CALIBRATION......................................................................................................... 27
5.1. Calibration Specifications...................................................................................27
5.2. Frequency Recommendations ...........................................................................27
5.3. Calculating the Span Gas Value ........................................................................28
5.4. Calibrating the On-Board Sensor .......................................................................29
5.5. Calibrating a Second On-Board Sensor .............................................................30
5.6. Calibrating a Remote Solid-State Sensor...........................................................30
5.7. Calibrating 4-20 mA Signal for Incoming Analog Transmitter .............................32
6. SYSTEM MAINTENANCE........................................................................................ 33
7. COMMON ACCESSORIES, OPTIONS, AND REPLACEMENT PARTS .................. 34

GDC-350 Operation Manual
5909-9000 Rev 1 1
1. OVERVIEW
1.1. General Description
The GDC-350 is an economical, self-contained gas detector for non-hazardous (non-
explosion rated) commercial applications. It is available in two basic configurations:
single-sensor models and dual-sensor models. The sensors can be configured as
one of the following:
xone on-board (A type)
xone remote (B type)
xone on-board and one remote (D type)
xtwo on-board (E type).
A basic system provides LEDs to indicate Power, Fail, Low (Warning) Gas Alarm, and
High Gas Alarm. Also included are an integral audible alarm with door-mounted
silence push-button, audible time delay, field-settable relay time delays and two alarm
relays.
Gas-specific electrochemical sensors for toxic gases and oxygen are available while
MOS solid-state sensors for combustible gases, TVOCs, and refrigerants are also
available. All GDC-350 on-board sensors are packaged as plug-in “smart” sensor
modules to reduce field maintenance time.
1.2. Key Exterior Components
Figure 1-1. Standard GDC-350 Components
NOTE: Photos of the GDC-350 in this manual may show the optional
LED digital display and/or the optional splash guard.

GDC-350 Operation Manual
2 5909-9000 Rev 1
Figure 1-2. Water Tight GDC-350 Components
1.3. Key Interior Components
Figure 1-3. Interior Components of the GDC-350

GDC-350 Operation Manual
5909-9000 Rev 1 3
1.4. Sensor Aging and Calibration Extending Firmware (CEF)
GDC-350 systems with on-board electrochemical sensors have been programmed
with our CEF (Calibration Extending Firmware). This firmware takes into
consideration the aging of the electrochemical CO, NO and NO2sensors so that less
frequent calibrations are acceptable in non-critical applications such as parking
garages. The system tracks the age of the sensor and automatically compensates for
the degraded output of the sensor as it ages.
2. SPECIFICATIONS
2.1. Controller Specifications
Categories/Subcategories Descriptions
Enclosure
Type Standard (NEMA 1X) Water Tight (NEMA 4X)
Dimensions
H x W x D
5.25 x 6.75 x 2.63 (in)
133 x 172 x 67 (mm)
5.13 x 7.13 x 4.00 (in)
130 x 181 x 102 (mm)
Weight 1.2 lbs (0.6 kg) 1.4 lbs (0.7 kg)
Construction
Polycarbonate with
hinged, secured door
(drip resistant)
Polycarbonate with
hinged, secured door
(water tight)
Wiring
Power 24 V (nominal), DC or AC (50/60 Hz)
Remote
Sensor
500’ maximum distance between controller and
remote sensor using minimum 18 gauge wire
User
Interface
Display
Common set of LED indicators (4) for:
Power, Fail, Low (Warning) Gas Alarm,
High Gas Alarm
Sensor indicators (2) for:
Sensor 1, Sensor 2
4-digit 8-segment LED digital display (optional)
Audio Integral alarm rated 80 dB @ 10’
Buttons Push-button to silence audible alarm
Relays Two DPDT dry-contact relays (rated 5 A @ 240 VAC)1
Control
Settings
2
Relays
(DIP Switch)
Low Gas Alarm “On” Delay (on “make”) 5 min
Low Gas Alarm “Off” Delay3
High Gas Alarm “On” Delay (on “make”) 5 min
(on “break”) 10 min
Audio Audible Alarm “On” Delay (on “make”) 5 min
Audible Alarm Feature (on/off)
Environ-
mental
Temperature 0° to 40° C (32° to 104° F)
Humidity 0 to 95% RH non-condensing
1System is configured such that all relays are “FAIL SAFE” (relay coils are always
energized in non-alarm state). Relays are “common” to both channels (activated by
either channel).
2May be set by user
3Also known as “minimum run time”

GDC-350 Operation Manual
4 5909-9000 Rev 1
Figure 2-1. Standard Enclosure Dimensions
Figure 2-2. Water-Tight Enclosure Dimensions

GDC-350 Operation Manual
5909-9000 Rev 1 5
2.2. Sensor Specifications
Categories/Subcategories Descriptions
On-Board
Sensors
Electrochemical1
Response: <30 seconds to 90% of signal
response
(Gas Specific)
Temp Range: 0° C to +50° C (operating)
Repeatability: ±10% of set point
Life Span: 2 to 3 years in air (under normal
conditions)
Gases: CO, NO, NO2, SO2(gas-specific)
Temperature Range: -20° to 40° C (-4° to 104° F)
Remote
Sensors
Solid-state
Combustibles
(Non-specific)
Response: <35 seconds to 90% of signal
response
Temp Range: 0° C to +40° C (operating)
Repeatability: ±10% of set point
Life Span: 5+ years in air (under normal
conditions)
Gases: E.g., Propane (C3H8), gasoline
vapors, methane (CH4) (non-
specific combustibles)
Solid-state
Refrigerants
(Non-specific)
Response: <120 seconds to 90% of signal
response
Temp Range: 0° C to +40° C (operating)
Long Term
Drift: < 5% signal loss / month at
ambient temperatures
Repeatability: ±10% of set point
Life Span: 4-5+ years in air
Typical
Refrigerant Gas
Sensors
Available: R11, R12, R22, R123,
R134A, R404A, R407C,
R410A, R422A, R422D,
R438A, and R507
Analog transmitter24-20 mA signal
1All integral electrochemical gas sensors are packaged as “Smart” sensor modules.
2Supports any 4-20 mA analog transmitter manufactured by Bacharach.

GDC-350 Operation Manual
6 5909-9000 Rev 1
2.3. Model Designations

GDC-350 Operation Manual
5909-9000 Rev 1 7

GDC-350 Operation Manual
8 5909-9000 Rev 1
3. INSTALLATION
3.1. Sensor Mounting Heights
Gas Applications / Types Suggested Mountings
Carbon Monoxide Gas engine exhaust
4’ to 6’ from the floor
Nitric Oxide Diesel engine exhaust
applications
Nitrogen Dioxide
Sulfur Dioxide All 6” from the floor or near likely
spot for leakage
Refrigerants All
Combustibles
Propane
Methane On/near ceiling (within 12”)
Hydrogen
NOTE: Bacharach considers 4 to 6 feet from the floor as the “breathing
zone” when it applies to sensors installed for vehicle exhaust
applications.
3.2. Basic Enclosure
There are two exterior
mounting brackets (one
at the top and one at the
bottom of the base of the
enclosure). These may
be used to mount the
enclosure.
Alternatively, there are
four corner mounting
holes in the enclosure.
Remove the screw
securing the hinged door.
Locate the four 3/16”
diameter mounting holes
located inside the system
enclosure base. Secure
the system to any flat
surface through these
mounting holes.
Figure 3-1. Basic Enclosure Mounting Components

GDC-350 Operation Manual
5909-9000 Rev 1 9
3.3. Remote Sensor Housing for Solid-State Sensors
Figure 3-2. Remote Sensor Housing
3.4. Detailed Wiring Connections (Types A, B, and D)
Figure 3-3. Wiring Connections for GDC-350 Types A, B, and D

GDC-350 Operation Manual
10 5909-9000 Rev 1
3.5. Detailed Wiring Connections (Type E)
Figure 3-4. Wiring Connections for GDC-350 Type E
3.6. Wiring the GDC-350 for Power
Drill out one or more of the PVC conduit entry hole plugs located at bottom left or right
or top left edge of system enclosure base. If supplying VAC operational power, pull
two wires suitable for low voltage from power source to the terminals 13 and 14. If
supplying VDC, wire to terminals 12 and 13 observing polarity.
Figure 3-5. Proper Wiring Examples

GDC-350 Operation Manual
5909-9000 Rev 1 11
Figure 3-5. Proper Wiring Examples (Continued)

GDC-350 Operation Manual
12 5909-9000 Rev 1
Figure 3-6. Improper Wiring Example
3.7. Wiring Remote Sensors (Voltage and Signal)
Three (3) conductor, 16 to 18 gauge, stranded wire is required between the control
panel and the remote solid-state sensor. Under most local electrical codes, low
voltage wires cannot not be run within the same conduit as line voltage wires. 3-
conductor, 16 to 18-gauge wire/cable must be shielded when connecting to a remote
analog transmitter. The remote analog transmitter enclosures have several conduit
entry locations (general purpose enclosure).
NOTE: DO NOT use solid-core wire for connection to wiring terminal
strip. Any damage caused by using solid-core wire will void warranty.
Use stranded wire ONLY.
The voltage supplied by the controller to remote solid-state sensors should measure
approximately 5.0 VDC ±2%, at the remote sensor. Voltage supplied by the controller
to remote analog transmitters should measure approximately 24 VDC nominal. This
voltage is factory set at time of manufacturing. If these voltages are not attained after
installation, the wrong gauge wire may have been used or the wiring run is too long.
The maximum distance between the GDC-350 and the remote sensor is 500 feet.
The remote solid-state sensor housing has a 3/4” conduit thread and nut to allow
installation in any standard electrical junction box (to be supplied by the installer).
Connect three low voltage wires between it and the controller and observe polarity.
3.8. Wiring Relay Connections
System relays are dry contacts and designed to operate fan starters or coils to control
equipment that draws more than 5 amps start-up and/or operational current. The
system does not provide any power from these terminals. Dry contacts operate like a
switch to simply activate (switch on) or de-activate (switch off) equipment to be
controlled, such as fan starters.
NOTE: System relays are SPDT (single pole, double throw) thereby
providing one set of usable dry contacts for each relay. Because the
GDC-350 series systems are designed to be fail-safe, any equipment to
be controlled by the system relays should be wired to the “NC” Normally
closed) and “COM” (Common) terminals. The relay coils are normally
energized in non-alarm state for fail-safe operation.

GDC-350 Operation Manual
5909-9000 Rev 1 13
3.9. Installation Example 1: Type “A” with Enclosed Transformer
Figure 3-7. Sample Type “A” Installation

GDC-350 Operation Manual
14 5909-9000 Rev 1
3.10. Installation Example 2: Type “B” with Remote Solid-State Sensor
Figure 3-8. Sample Type “B” Installation
NOTE: Wiring between a GDC-350 and the remote sensor (indicated
above) should be 3-conductor, 16 to 18-gauge shielded cable. Observe
polarity because the GDC-350 supplies DC power to the remote sensor.