Bacharach HGM-MZ Operating instructions

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
BACHARACH Inc.
HGM-MZ Multi-Zone Monitor
Annual Maintenance
And Troubleshooting Guide
Service, Testing and Maintenance procedures

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
HGM-MZ
Routine Annual Maintenance
And Operating Parameter Verification
These maintenance and service items and procedures below will be
referenced in the tech bulletins and operations manual and used by
customer service and technical support technicians when discussing parts
or service of the refrigerant monitor. Using this information allows the
installation technician to quickly identify the service points and make
maintenance measurements and adjustments to the unit quickly and
accurately.
Yearly maintenance is required to assure peak performance and accuracy
of the HGM-MZ multi-zone monitor. If the monitor is installed in areas of
high levels of dust and particulate it is recommended that semi-annual or
quarterly filter changes be made to prevent system faults due to purge or
zone restrictions.
During these maintenance procedures it is a good time to check the
diagnostic screen “DIAG” to verify that the detector voltage and pump
pressures and within optimum parameters. If they are not a voltage
adjustment or scheduled pump replacement could head off a system fault.
To verify monitor operation it is possible to use a bump gas test using
keyboard cleaner (dust destroyer) which is typically R134a purchased at
your local office supply store. If calibration type verification is required we
have “Gas Verification kits available which contain certified PPM levels of
test gas.
Please refer to the Tech Bulletins on the following pages for parts
identification, actual settings and adjustment sequence.

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
HGM-MZ
Detector voltage and Reference voltage
adjustment.*
*Only If Required
Correcting and adjusting; Fault codes, Gain Set 200, Over
Range 2000, Zero 4000 and Clipping 8000
Figure 1
To correct for codes 200, 2000, 4000 and
8000 – from the front screen on the HGM
MZ select the top left block (under
STATUS) and press enter. This will take
you to the SETUP screen.
To enter service mode:
From the main sampling screen (figure 1) press enter two times that will take you to the SETUP
screen (figure 2) then move the cursor to the Service Mode entry box, then press enter, it will now
say (service mode confirm), press enter again, it will now say, (service mode quit), press enter
again, it will now say (service confirm quit), press enter again and if you did it correctly it will say
(service mode entry) again.

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
Figure 2
At the setup screen you can view the current conditions by entering the diagnostic
screen “DIAG”. To make changes and adjustments you must first put the monitor in the
SERVICE MODE. Once in service mode select “SYSTEM”.
To access detector voltage and IR
voltage adjustment screen select
SERVICE MODE ENTRY – press
enter twice then select SYSTEM
and press enter.
To enter service mode:
From the main sampling screen (figure 1) press enter two times that will take you to the SETUP
screen (figure 2) then move the cursor to the Service Mode entry box, then press enter, it will now
say (service mode confirm), press enter again, it will now say, (service mode quit), press enter
again, it will now say (service confirm quit), press enter again and if you did it correctly it will say
(service mode entry) again.

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
In the “SYSTEM SETUP” arrow down to “MORE” and press enter to get to the actual
adjustment screens.
In the “MORE” screen you have access to the “DET DIGIPOT” and “IR DIGIPOT”
voltage adjustments. Select the item you want by highlighting it and hitting enter. To
adjust and use the arrow keys move to it, then press enter which will allow you to see
the voltage and make the adjustments with the up and down arrow keys.
The detector digipot “DET DIGIPOT” voltage range should be between 4.20 to 4.28
VDC with the digipot three digit reference numbers between 120 and 255.
In the SYSTEM SETUP select
MORE and press ENTER to
get to the adjustment screens.
Record the DET DIGIPOT and
IR DIGIPOT readings for
reference.
Highlight DET DIGIPOT and
press enter to view the Digipot
and IR VOLTAGE.
Highlight IR DIGIPOT and
press enter to view the IR
VOLTAGE.

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
Note - Go into IR DIGIPOT and
verify that the MW is not set outside
the range of 300 to 500 after
adjusting the IR detector voltage IR
DIGIPOT. A typical MW setting for a
sensor with Yellow tape is 325
without the tape it is approx 425.
To adjust the MW use
the up and down arrow
keys on the keypad.
Adjust the Detector Digipot Voltage
Range 4.20 to 4.28 with up and down
Sensor
No Tape
With
Digipot Reference
b

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
HGM-MZ Sample pump flow testing
This procedure describes the correct method for testing the sampling pump in order to
determine its proper sample flow and vacuum.
HGM-MZ Pump Testing;
If the HGM- MZ is unable to pull a vacuum it will generally be due to one of two things, either the
pump is not running or failed, or there is a leak in a valve or valve stuck open in the manifold.
Flow detection is based on a minimum drop from ambient pressure and a minimum value above
vacuum, so a vacuum failure will generally result in a NO flow indication on all zones.
The pinch test can isolate the problem quickly. In the diagnostic screen observe the live
pressure "PRES", then pinch the tube on one side of the white disc (Hydrophobic filter) pinching
either side is OK. This will dead head the pump, a good pump will drop the pressure to
approximately 3 psia below the Ambient reading. If you get no change, the pump is not
working, the “EXHAUST” port is restricted, or there is a leak between the pinch point and the
pump.
If the pinch yields a good vacuum number, the problem is before the pinch in the valve
manifolds. One or more manifold valves are either stuck open or a failed valve driver board is
electrically holding it open. (See separate tech Bulletin on Manifold testing procedure)
Pump Pressure (PRES)
Pump Vacuum (VAC)
Ambient Air Pressure (AMB)
Indicates good or bad pump
operation
Enter Diagnostic Screen (DIAG)
From SETUP Screen

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
HGM-MZ
Major Parts List with Part Numbers
Sampling Pump with
Connector 3015-5176
Rabbit Processor
Board
Hydrophobic Filter
07-1650
Battery
0204-
0020
Infrared Bench Replacement
Kit 3015-4572
Power Supply Board
3015-5149
Power
Entry
Board w
Fuse
Manifold Control Board
3015-5095
Main
Processor
Board
(Motherboar
d)
Replaceme
nt Fuses
(2)
0004-2620
Manifold Block w/ Purge
3015-5080
4 port manifold (not shown)
3015-5072
Plug in points for
optional dual 4-20
communications board
10 pin Ribbon
cable
3015-4258
12 pin
Ribbon
cable
Note: this sensor is
shown without the
YELLOW TAPE around

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
Inside Cover View
Filters
3015-3125 Charcoal Filter Assembly with Fittings
3015-5931 Display PC
Board and Keypad PC
Board Kit
(With interconnecting
Ribbon Cable)
3015-5182 Ribbon Cable - Main
PCB to Keypad Board

Bacharach | THE MEASURABLE DIFFERENCE | New Kensington, PA, USA | Dublin, Ireland | Toronto, Canada | mybacharach.com
Figure 1
07-1650
Hydrophobic Filter
Figure 2
3015-2906
Line end filter only
Figure 3
3015-3420
Line End Filter Assembly
Figure 4