Martel Electronics DPC300A User Manual

DPC300A

Reference Manual

DPC300A
Reference Manual

1. Introduction ........................................... 1

1.1 Customer Service .........................................1

1.2 Standard Equipment .......................................1

1.3 Safety information ........................................2

2. Calibrator Interface ..................................... 5

2.1 Calibrator Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.2 Using the Backlight........................................9

2.3 Using the Zero Function ....................................9

2.4 Other Menu Controlled Functions ...........................10

3. Initial Setup and Basic Pressure Generation ............... 14

4. Measuring pressure.................................... 15

4.1 Media compatibility.......................................15

4.2 Measuring pressure with external modules ....................16

4.3 Measuring and sourcing current (4 ... 20 mA) ..................16

4.4 Measuring voltage .......................................17

4.6 Calibrating transmitters....................................20

5. Minimum and Maximum Storage Capability ................ 25

6. Remote Operation ..................................... 26

6.1 Remote Interface ........................................26

6.2 Setting up the RS-232 Port for Remote Control .................26

6.3 Changing Between Remote and Local Operation ...............27

6.4 Using Commands ........................................28

6.5 Remote Commands and Error Codes ........................30

6.6 Entering Commands ......................................32

7. Specifications (15 °C to 35 °C unless otherwise noted.) ...... 40

9. Maintenance .......................................... 41

9.1 Cleaning the Unit ........................................41

9.2 Service Center Calibration or Repair .........................41

1. Introduction

The DPC-300A is a high accuracy portable pressure source that can
accurately source pressure from internal and external pressure
supplies. The product includes two pneumatic pressure sources.
One source is an automated internal, -12 to 300 psi (-0.8 to 20 bar)
pump and the other is connection to allow the regulation of
externally supplied clean dry air (shop air up to 120psi). In addition
to pressure generation and measurement, the unit has full electrical
measurement capabilities from 0 to 24mA and 0 to 30VDC. It also is
able to generate 4 to 20mA signals and a full-time 24 volt loop power
supply is always available utilizing dedicated jacks on the front
panel. Additional pressure ranges can also be supported through
the use of external pressure modules. The unit can be powered by
an internal, high capacity, rechargeable battery or the included AC
adapter/charger.

1.1 Customer Service

Corporate Office:

www.martelcorp.com

e-mail: [e-mail]

Tel: [phone] Fax: [phone]

Martel Electronics
3 Corporate Park Dr.

Derry, NH 03038

1.2 Standard Equipment

Check to see if your calibrator is complete. It should include: DPC­300A, instruction manual, test leads, calibration hose kit with fittings,
16V Universal AC charger, Nist traceable calibration certificate.

1

1.3 Safety information

Symbols Used

The following table lists the International Electrical Symbols. Some or
all of these symbols may be used on the instrument or in this
manual.

Symbol Description

AC (Alternating Current)

AC-DC

Battery

CE Complies with European Union Directives

DC

Double Insulated

Electric Shock

Fuse

PE Ground

Hot Surface (Burn Hazard)

Read the User’s Manual (Important Information)

Off

On

Canadian Standards Association

2

2

The following definitions apply to the terms “Warning” and “Caution”.

• “Warning” identifies conditions and actions that may pose hazards

to the user.

• “Caution” identifies conditions and actions that may damage the

instrument being used.

Use the calibrator only as specified in this manual, otherwise injury
and damage to the calibrator may occur.

Warning

To avoid possible electric shock or personal injury:

• Do not apply more than the rated voltage. See specifications for

supported ranges.

• Follow all equipment safety procedures.

• Never touch the probe to a voltage source when the test leads are

plugged into the current terminals.

• Do not use the calibrator if it is damaged. Before you use the

calibrator, inspect the case. Look for cracks or missing plastic. Pay
particular attention to the insulation surrounding the connectors.

• Select the proper function and range for your measurement.

• Make sure the battery cover is closed and latched before you

operate the calibrator.

• Remove test leads from the calibrator before you open the battery

door.

• Inspect the test leads for damaged insulation or exposed metal.

Check test leads continuity. Replace damaged test leads before
you use the calibrator.

• When using the probes, keep your fingers away from the probe

contacts. Keep your fingers behind the finger guards on the
probes.

• Connect the common test lead before you connect the live test

lead. When you disconnect test leads, disconnect the live test lead
first.

• Do not use the calibrator if it operates abnormally. Protection may

be impaired. When in doubt, have the calibrator serviced.

• Do not operate the calibrator around explosive gas, vapor, or dust.

• When measuring pressure, make sure the process pressure line is

shut off and depressurized before you connect it or disconnect it
from the pressure module.

• Disconnect test leads before changing to another measure or

source function.

33

• When servicing the calibrator, use only specified replacement

parts.

• To avoid false readings, which could lead to possible electric

shock or personal injury, replace the battery as soon as the battery
indicator appears.

Caution

To avoid possible damage to calibrator or to equipment under test:

• Use the proper jacks, function, and range for your measurement or
sourcing application.

4

4

2. Calibrator Interface

Figure 1 shows the location of the pressure controls, connection port
and electrical inputs.

Figure: external pressure supply

MAX 120 PSI

0-100 PSI

-12-300 PSI

OUTPUT

0-100 PSI
OUTPUT

-12-300 PSI

PUMP

PUMP

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

SELECTOR

PUMP

SELECTOR

CHARGE

PUMP

0 to 120 psi

Air Supply

CHARGE

PRESSURE

DPC-300A

[P1]

psi

30.00

MODULE

MENU LOWER LIGHT

MARTEL ELECTRONICS

F2 F3

F1

HOME

ZERO

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P2

P4

MAIN

SELECTOR WARNING:

Air Supply Mode

Figure: Pressure supply with integrated pump

MAX 120 PSI

DPC-300A

[P1]

psi

30.00

PRESSURE

MODULE

MENU LOWER LIGHT

MARTEL ELECTRONICS

F2 F3

F1

HOME

ZERO

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P2

P4

MAIN

SELECTOR WARNING:

PRESSURE

Air Supply Mode

Figure: Measuring

MAX 120 PSI

0-100 PSI

-12-300 PSI

DPC-300A

[P1]

psi

300.00

MODULE

MENU LOWER LIGHT

MARTEL ELECTRONICS

F2 F3

F1

HOME

ZERO

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P2

P4

MAIN

SELECTOR WARNING:

Measurement Mode

-12-300 PSI

OUTPUT

PUMP

MEASURE

CHARGE

FINE ADJUST / VENT

-12 to 300 psi

PRESSURE VACUUM

PUMP

SELECTOR

VENT BEFORE SELECTION

Pressure Source

5

5

Figures 2A and 2B show the location of the keys. Table 2 describes the
function of each key.

Figure 2A

Keypad

Table 2 Key Functions

No. Name Description

1 Function Keys These are soft keys used to configure the calibrator

2 ON/OFF Key This key is used to turn the calibrator on and off

3 ZERO Key This key is used to zero pressure measurements

4 Arrow Keys Used to control mA source/sim. and to set pump

and % error limits

5 Home Key Return to main menu screen

6 Pump Key Push to run pump (Electric pump version)

Note: When the calibrator is turned on by pressing the ON/OFF key,
it will go through a short startup self-check routine. During that
routine, the display shows the current firmware revision level, auto
shutdown status and the range of the internal pressure sensor. The

calibrator requires a maximum of 5 minutes warm-up to rated
accuracy. Large changes in ambient temperature may require a

longer warm-up period. See section 2.3 for instructions on zeroing
the pressure sensor displays. Pressure ranges should be zeroed
each time the calibrator is started.

66

2.1 Calibrator Display

The Calibrator Display consists of two regions: The menu bar
(located along the bottom of the screen) is used to access a menu
system. The main display (the rest) consists of up to three process
measurement sub-regions. These sub-regions will henceforth be
referred to as the UPPER, MIDDLE and LOWER displays. Figure 3
shows the location of the different display fields while table 3
describes them.

[P1]

psi

1

30.000

3

mA MEASURE 100.00%

2

20.000 mA

CONFIG LOWER MORE

Figure 3

Display

Table 3 Display Functions

No. Name Description

1 Pressure units Indication of the pressure unit (selectable from

13 pressure units)

2 Span Indicator Indicates the percent of the 4 to 20 mA span.

(For mA and mA Loop functions only)

3 Primary parameter Indicates current measured parameter

2.1.1 Top Level Menu Functionality

There are three options for this menu: MENU, {Active Display}, and
LIGHT. The Top Level Menu is home for the menu display.

2.1.1.1 Using the MENU Option

The MENU option is the gateway to the rest of the menu system.

2.1.1.2 Using the Active Display Option

The active display is indicated by the center option on the Top Level
Menu. It is used to select the display to which the ZERO key will
apply.

2.1.1.3 Using the LIGHT OPTION

The backlight can be toggled on and off using this key.

7

7

2.1.2 Main Menu Functionality

There are three options on the Menu, CONFIG, {Active Display} and
MORE. The Main Menu is home for the menu display.

2.1.2.1 Setting the Active Display

The active display is indicated by the center option on the Main
Menu, pressing the F2 key will toggle the active display.

2.1.2.2 Setting Active Display Parameters

To set the parameters of the active display use the CONFIG option to
get to the Display Configuration Menu.

Here the SELECT option will toggle through the choices for each
parameter. The first parameter is MODE. Since voltage, current and
switch test modes all use the same jacks, two of these functions
cannot be used concurrently. The ability to select certain functions is
limited based on what is already selected in another display. The
NEXT option is used to change to the second parameter. Only
Pressure modes have a second parameter. Pressure can be read in
11 engineering units.

With a single display the following modes are available:

P[1] = Pressure internal sensor.

[EXT] = Pressure with external pressure module.

P[1] ST = Switch Test with left side sensor.

[EXT] ST = Switch Test with external pressure module.

Note: mA functions are only available on the Lower Display.

mA measure = Milliamps measure.

mA source = Milliamps source.

mA sim = Milliamps simulate using an external supply from the
UUT.

VOLTS = Voltage Measure.

The following table shows which functions are available concurrently.

An X in a column indicates that the mode in the active display will be
available for selection if the mode in that row is in use in any other

display.

8

8

Table 4 Mode Concurrency

Active Display

P[1] [EXT] P[1] ST[EXT]STmA mA

P[1] X X X X X X X

[EXT] X X X X X X X

P[1]ST X X

[EXT]ST X X

mA X X X

Other Displays

mA Loop X X X

Volts X X X

X = valid mode

2.1.1.3 Accessing Other Menus

Use the MORE option on the Main Menu to access the other menu
functions.

2.2 Using the Backlight

The backlight is controlled by the LIGHT softkey on the main menu.
It toggles on and off when the key is pressed; this is one of the few
functions that cannot be controlled by the serial interface. There are
no user configuration settings for the backlight.

Volts

Loop

2.3 Using the Zero Function

When the ZERO KEY is pressed, the calibrator will zero the active
display if a pressure mode is selected, and the pressure is within

the zero limit. The zero limits are within 10% of the full scale range of
the selected sensor. If the display indicates “OL,” the zero function
will not operate.” Note: The ZERO KEY is only used for pressure.

2.3.1 Internal Sensor and Pressure Module (non-absolute)

When a sensor or module is selected on the active display and the
ZERO KEY is pressed the calibrator subtracts the current reading
from the output. The zero limits are within 10% of the full scale range
of the selected sensor. If the display indicates “OL,” the zero function
will not operate.

2.3.2 Absolute Pressure

When an absolute pressure range is selected on the active display
and the ZERO KEY is pressed the calibrator prompts the user to
enter the barometric reference pressure. This is done using the

9

9

arrow keys (F2 and F3 Keys). The sensor port should be open
(vented) to atmosphere while performing this procedure.

2.4 Other Menu Controlled Functions

There are many ‘sub-main’ menus that can be accessed through the
MORE option of the Main Menu. A ‘sub-main’ menu contains three

options. The first option is unique to the function. The second and

third options of a ‘sub-main’ menu are always the same. The NEXT
option leads to the next ‘sub-main’ menu and the DONE option
returns home . For the last ‘sub-main’ menu the NEXT option wraps
around to home. See Figure 4 for a detailed mapping of the menu
structure.

A note on naming convention:

If a ‘sub-main’ menu has subordinate menus, it will henceforth be
referred to as {function} Main Menu. E.g. the display contrast sub­main menu will be called the Contrast Main Menu. If not it will be
called the {function} menu.

2.4.1 Setting the Contrast

From the Contrast Main Menu choose the CONTRAST option to
access the Contrast Adjustment Menu.

Use the F2, F3 keys to adjust the display contrast to the desired level
and then use the CONTRAST DONE option to return home.

2.4.2 Locking and Unlocking Configurations

Use the LOCK CFG or UNLOCK CFG option of the Configuration
Lock Menu to lock or unlock the display configuration.

When the LOCK CFG option is chosen the menu display returns
home and the CONFIG option on the Main Menu indicates that it is
locked. Also all menus are locked out with the exception of the Min

1010

Max Menu, Contrast Adjustment menus and the Configuration Lock
Menu. When the UNLOCK CFG option is chosen the configuration
is unlocked and the menu display continues to the next sub-main
menu.

2.4.3 Saving and Recalling Setups

The calibrator will automatically save the current set-up for recall at
power-up. Additionally 5 set-ups can be accessed through the
SETUPS menu. Select the SETUPS option from the Setups Main
Menu.

Choose SAVE to save a set-up , RECALL to recall the set-up, or
DONE to do nothing and return home.

1111

12

12

Figure 4

Menu Map

If SAVE or RECALL is selected use the arrow keys to select the set­up location. Then use the save option to store the current set-up
into the selected location or the recall option to recall the set-up
stored in the selected location. The display menu will automatically
go home.

2.4.4 Setting AutoShut-off Parameters

The calibrator can be set to automatically shut-off after a selected
number of minutes; this function can also be disabled. To set the
auto shut off parameters select the AUTO OFF option on the Auto
Shut Off Main Menu.

Use the F2, F3 keys to select the number of minutes before the
calibrator turns off or disable auto shut-off by scrolling all the way
down.

Use the AUTO OFF DONE option to set the parameters and return
home. The auto shut off time is reset whenever a key is pressed.

2.4.5 Activating and Deactivating a Display

Use the DISPLAY option on the Display Selection Main Menu to
access the Display Activation Menu.

The {display} option can be used to select which display to act
upon. The ON/OFF option turns the selected display on or off. The
selected display and current on/off state are displayed in the lower
display.

1313

Use the DONE option to save the changes and return home. When
a display is deactivated its configuration is retained. When the
display is activated its configuration is checked against the
configurations of the other currently active displays, if the
configurations are in conflict the recalled display’s configuration is
modified to avoid the conflict. If all three displays are deactivated the
LOWER display will come on automatically

2.4.6 Damping

Damping can be turned ON or OFF using the Damping menu
selection. When damping is ON, the calibrator displays an running
average reading of ten measurements. The calibrator makes
approximately 3 readings per second.

2.4.7 Pump Limits

To prevent overpressure of sensitive devices the maximum pressure
(pump limit) can be set. When in this mode use the arrow keys to set
the maximum pressure.

2.4.8 HART™ Resistor

An internal 250 ohm HART Resistor can be enabled when the
BetaGauge 330 is operated in the “mA Measure-24V” mode. This
allows a HART Communicator to be connected across the mA
terminals and eliminates the need for adding an external resistor.

Note: When the HART resistor is on the maximum load driving
capacity is 750 ohms.

3. Initial Setup and Basic Pressure Generation

1. The DPC-300A is supplied with a special low-volume calibration

hose to enable faster pressure generation and quick pressure

stabilisation. Included in delivery are "Quick-fit" hose connectors
and various adapters. It is recommended that this hose is used in
order to achieve the best results. As soon as the fittings are
installed and the calibrator is connected to the test item the
calibrator is ready for use.

2. The pressure calibrator must be configured for the appropriate

application (see chapter 6).

14

14

3. Set the pressure/vacuum selection knob to the desired function
(+ for pressure and - for vacuum).

4. Close the vent knob.

5. Press the pump key and monitor the pressure rise (or vacuum
generation) until you reach the desired pressure.

Note: The motor speed will start slowly while the pressure is
low (< 1 bar) to enable better control at low pressures.

6. The fine pressure adjustment enables the pressure to be set
precisely.

7. To reduce or bleed off the pressure entirely slowly rotate the vent
knob to the open position. The pressure reduction is best
controlled if this step is carried out carefully and it makes reading
the pressure easier.

4. Measuring pressure

For pressure calibration, connect the calibrator with an appropriate
adapter. Select the pressure setting for the display being used. The

calibrator is equipped with an internal sensor and optional external

sensors are available. Choose a sensor that is suitable for the
pressure range and accuracy.

CAUTION!

Pressure sensors may be damaged and/or injuries may occur to the
personnel due to improper application of pressure. For a better
understanding with respect to overpressure and burst pressure,
follow the specifications laid down in these operating instructions
(see chapter "3. Specifications"). The calibrator display will indicate
"OL" when an inappropriate pressure is applied. As soon as "OL" is
observed on any pressure display, the pressure should be reduced
immediately to prevent damage or possible physical injury. "OL" is
displayed if the pressure exceeds the nominal range by 110 %. Use
the ZERO key to zero the pressure sensor once it is vented to
atmospheric pressure.

4.1 Media compatibility

CAUTION!

The calibrator should only be used with clean, dry gases! To prevent
contamination by the test pieces, the use of a dirt trap is
recommended (see chapter "10. Accessories")!

15

15

4.2 Measuring pressure with external modules

The calibrator has a digital interface for external pressure modules.
These modules are available for various ranges, including gauge,
vacuum, differential and absolute pressure. The modules work
seamlessly in conjunction with the calibrator. Simply plug them into
the interface and select [EXT] (external sensor). Since the interface
between the calibrator and the module is digital, the accuracy and
display resolution is dependent on the module.

MAX 120 PSI

0-100 PSI

-12-300 PSI
PUMP

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

PRESSURE

MODULE

DPC-300A

MARTEL ELECTRONICS

F2 F3

F1

HOME

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

AIR SUPPLY

OUTPUT

P1 P2 P3 P4

FILTER

REGULATOR

ZERO

J3

P3

P2

MAIN

SELECTOR WARNING:

P4

PUMP

SELECTOR

CHARGE

Valve

Pressure Module
Adapter

Pressure Module

4.3 Measuring and sourcing current (4 ... 20 mA)

1. To measure current, use the input terminals on the front of the
calibrator. Select the mA function on the lower display. Current is
measured in mA and percentage of the measuring range. The
measuring range on the calibrator is set to 0 % at 4 mA and 100 %
at 20 mA.

Example

If the current measured is displayed as 75 %, then the value is 16
mA.

Note: The display will indicate "OL" when the measured
current exceeds the nominal range of current measurement
(24 mA).

2. The same connections are used for the current source. Select
mA-Source or mA Sim-2W from the configuration display.

1616

3. This selection can only be made in the lower display. Also, in
source mode, the calibrator will generate 0 ... 24 mA using its own
internal 24 V supply, whereas in simulation mode the calibrator

acts as a 2-wire transmitter and requires an external 24 V supply.

4. Pressing any of the arrow keys will start the output mode and
enable you to use the arrow keys to adjust the mA output. The
function keys can also be used to progress the output in either 25
% steps (4, 8, 12, 16, 20 mA) or 0 % (4 mA) and 100 % (20 mA).

5. While in the mA output mode, if the loop is broken or the
resistance burden is exceeded, the calibrator will flash "OL".

mA MEASURE

75.00%

PUMP

16.000 mA

CONFIG LOWER MORE

mA SOURCE

100.00%

20.000 mA

MENU LOWER LIGHT

mA SIM-2W

100.00%

20.000 mA

MENU LOWER LIGHT

mA MEAS/24V

100.00%

20.000 mA

MENU LOWER LIGHT

COM

SWITCH TEST +24v DC

J1 J2

COM

SWITCH TEST +24v DC

J1 J2

COM

J1 J2

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

VOLTS /mA

J3

PUMP

VOLTS /mA

J3

PUMP

VOLTS /mA

SWITCH TEST +24v DC

PUMP

J3

4...20 mA

4...20 mA

–

Test Item

J3

4...20 mA

Test Item

Test Item

+

+

–

Power Supply

DC 24 V

4...20 mA

Test Item

4.4 Measuring voltage

For voltage measurement, use the connections on the front of the
calibrator. Select the VOLTS function on one of the displays. The
calibrator can measure up to DC 30 V.

1717

Note: The display will indicate "OL" when the measured
voltage exceeds the nominal range of voltage measurement
(30 V).

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

PUMP

J3

VOLTS

30.000 V

CONFIG LOWER MORE

4.5 Performing a Pressure Switch Test

MAX 120 PSI

0-100 PSI

-12-300 PSI

OUTPUT

PUMP

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

PUMP

SELECTOR

CHARGE

PRESSURE

MODULE

MARTEL ELECTRONICS

F2 F3

F1

HOME

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

REGULATOR

P3

AIR SUPPLY

P1 P2 P3 P4

FILTER

P4

DPC-300A

ZERO

P2

MAIN

SELECTOR WARNING:

J3

Up to DC 30 V

Test Item

Use low volume
hose if possible

Pressure
Switch

Figure 4: DPC-300A with pressure switch

To perform a switch test, the following steps must be taken:

1. The upper display is set to [P1] ST, all other displays are switched
off.

Note: The pressure switch test can be performed with the
following functions [P1] ST or EXT ST.

2. Connect the calibrator to the pressure switch using the switch
terminals. The polarity of the terminals does not matter. Then
connect the pump to the calibrator and the pressure switch.

3. Open the vent button on the pump and zero the calibrator. Then
close the vent after resetting the calibrator.

4. The top of the display will indicate "CLOSE".

1818

5. Apply pressure with the pump slowly until the switch opens.

Note: In the switch test mode the display update rate is
increased to help capture changing pressure inputs. Even
with this enhanced sample rate the device under test
should be charged slowly with pressure in order to ensure
accurate readings.

6. Once the switch is open, "OPEN" will be displayed; bleed the
pump slowly until the pressure switch closes.

7. In the top display it will now read "SW OPENED AT" and give you
the pressure at which the switch opened.

8. Select the "NEXT" option to display the pressure at which the
switch closed and the hysteresis.

1919

9. Select the "NEW TEST" option to clear the data and perform
another test.

10. Select the "DONE" option to end the test and return to the

standard pressure setting.

Example:

[P1] ST will return to [P1].

The previous example uses a normally closed switch. The
basic procedure is effectively the same for a normally open
switch, the display will simply read "OPEN" instead of
"CLOSE".

4.6 Calibrating transmitters

4.6.1 Using the mA measurement function

The mA function enables the user to read out the 4 ... 20 mA output
from the device being calibrated. This can be done in two ways.

1. Passively – the device under test generates 4 ... 20 mA directly.

This can be read on the calibrator.

2. Actively – the calibrator supplies a loop power of DC 24 V to the

device under test to

3. Power the device while reading the resulting 4 ... 20 mA signal.

2020

[P1]

psi

30.000

mA MEASURE 100.00%

20.000 mA

CONFIG LOWER MORE

Passive

[P1]

30.000

mA MEAS/24V 100.00%

20.000 mA

CONFIG LOWER MORE

Active

psi

4.6.2 Calibrating a pressure-to-current transmitter

To calibrate a pressure-to-current transmitter (P/I), perform the
following:

1. Connect the calibrator and the pump to the transmitter.

2. Apply pressure with the pump.

3. Measure the current output of the transmitter.

4. Ensure that the read value is correct. If it isn't, the transmitter must
be adjusted.

MAX 120 PSI

0-100 PSI

-12-300 PSI

-12-300 PSI

OUTPUT

PUMP

MEASURE

Use low volume
hose if possible

FINE ADJUST / VENT

PRESSURE VACUUM

PUMP

SELECTOR

VENT BEFORE SELECTION

CHARGE

PRESSURE

DPC-300A

MODULE

MARTEL ELECTRONICS

F2 F3

F1

HOME

ZERO

PUMP

P2

VOLTS /mA

COM

SWITCH TEST +24v DC

SELECTOR WARNING:

J1 J2

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P4

MAIN

Figure 5

4.6.3 Calibrating a pressure-to-voltage transmitter

To calibrate a pressure-to-voltage transmitter (P/V), perform the
following:

1. Connect the calibrator and the pump to the transmitter.

2. Apply pressure with the pump.

3. Connect the 24V to the transmitter.

3. Measure the voltage output of the transmitter.

4. Ensure that the read value is correct. If it isn't, the transmitter must
be adjusted.

21

21

MAX 120 PSI

0-100 PSI

-12-300 PSI

OUTPUT

PUMP

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

PUMP

SELECTOR

CHARGE

Signal Output

+24V Power

Pressure

Transmitter

Common

PRESSURE
MODULE

DPC-300A

VOLTS

30.000 V

CONFIG LOWER MORE

MARTEL ELECTRONICS

F2 F3

F1

HOME

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

ZERO

P3

P2

SELECTOR WARNING:

J3

P4

MAIN

Figure 6

4.6.4 %-Error function

The calibrator features a special function which can calculate the
error in the pressure value from the mA value as a percentage of the
4 ... 20 mA loop span. The %-Error mode uses all three screens and
has a special menu structure. It displays pressure, mA and %-Error
simultaneously.

MAX 120 PSI

0-100 PSI

-12-300 PSI

OUTPUT

PUMP

-12-300 PSI
MEASURE

FINE ADJUST / VENT

PRESSURE VACUUM

VENT BEFORE SELECTION

PUMP

SELECTOR

CHARGE

PRESSURE
MODULE

MARTEL ELECTRONICS

F2 F3

F1

HOME

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

DPC-300A

ZERO

P2

SELECTOR WARNING:

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P4

MAIN

2222

Use low volume
hose if possible

Figure 6: DPC-300A with a pressure transmitter

with %-Error function

Example:

Suppose a pressure transmitter under test has a full scale range of 2
bar and gives a corresponding 4 ... 20 mA output signal. The user
can programme in a 0 ... 2 bar pressure span into the calibrator and
the calibrator will then calculate and display the deviation or %-Error
value from the 4 ... 20 mA output. This then eliminates manual
calculations.

To use the "%-ERROR" function, perform the following:

1. Once the calibrator is switched on and operating, press the F3
key to activate the "MORE" menu option. Then press the F1 key to
activate the "%-ERROR" option.

2. Press the F1 key to select the "CONFIG" option.

3. The first option is the port setting. Use the "SELECT" option to
scroll through the choice of ports (pressure connections). Once
this is completed, select the "NEXT" option.

4. "LOOP POWER" can be toggled on or off; select "NEXT" when
done.

2323

5. Use "SELECT" to scroll through the "UNIT" options, and select
"NEXT" to move on.

6. Use the arrow keys to set the upper limit of the measuring range;
select "DONE SET" when finished.

7. Use the arrow keys to set lower limit of the measuring range, and
select "DONE SET" when finished. The "%-ERROR" mode will be
ready to use.

The lower and upper limit of the measuring range will be
saved in non-volatile memory until they are changed again
by the user for the internal sensors and the external
pressure modules.

2424

5. Minimum and Maximum Storage Capability

The 300 Series Pressure Calibrators have a min/max feature for
capturing the minimum and maximum values of any displayed
parameter.

The min/max function can be accessed by stepping through the menu
options until “min/max” is shown on the display above the F1 key. At
this time, pressing the F1 key will toggle the display through the min/
max values that are stored in the min/max registers. These readings
are live so that the new min/max values will be recorded while in this
mode.

To reset the min/max registers simply press the clear key. These
registers are also cleared at power-up or when the configuration is
changed.

2525

6. Remote Operation

6.1 Remote Interface

The calibrator can be remotely controlled using a PC terminal, or by
a computer program running the calibrator in an automated system.
It uses an RS-232 serial port connection for remote operation.

NOTE: To use the remote control option a custom RS-232
cable must be purchased from Martel (LEM232). To contact
Martel refer to Section 1.1 of this manual. With this connection

the user can write programs on the PC, with Windows languages like
Visual Basic to operate the calibrator, or use a Windows terminal,
such as Hyper Terminal, to enter single commands. Typical RS-232
remote configurations are shown in Figure 13.

MAX 120 PSI

0-100 PSI

-12-300 PSI

DPC-300A

PRESSURE

MODULE

MARTEL ELECTRONICS

F2 F3

F1

HOME

ZERO

PUMP

VOLTS /mA

COM

SWITCH TEST +24v DC

J1 J2

J3

AIR SUPPLY

P1 P2 P3 P4

FILTER

REGULATOR

P3

P2

P4

MAIN

SELECTOR WARNING:

-12-300 PSI

OUTPUT

PUMP

MEASURE

CHARGE

FINE ADJUST / VENT

PRESSURE VACUUM

PUMP

SELECTOR

VENT BEFORE SELECTION

Figure 13. Calibrator-to-Computer Connection

6.2 Setting up the RS-232 Port for Remote Control

Note: The RS-232 connection cable should not exceed 15m unless
the load capacitance measured at connection points is less than
2500pF.

Serial parameter values:

9600 baud

8 data bits

1 stop bit

no parity

Xon/Xoff

EOL (End of Line) character or CR (Carriage Return) or both

The LEM232 cable is used for RS-232 communications from the
calibrator to a computer. If the computer only has USB type ports, a
USB to RS-232 converter will be needed. These can be obtained

26

26

from most office supply and computer stores. To connect the
calibrator to the computer, attach the LEMO connector end of the
cable to the pressure module port on the right side of the calibrator
and the DB-9 connector to the RS-232 port on the computer. The
calibrator should be turned off prior to making the connection and
then turned on.

To set up remote operation of the calibrator on the Windows Hyper
Terminal, connected to a COM port on the PC as in Figure 23, use
the following procedure:

1. Start Hyper Terminal (located in Accessories/Communications of
the Windows Start menu)

2. Select New Connection.

3. For Name enter Beta 330. Select the serial port that the calibrator
is connected to.

4. Enter the above information for port settings.

5. Select ASCII setup from File/Properties/Settings and mark these
choices:

Echo typed characters locally

Wrap lines that exceed terminal width

6. Select Ok

7. To see if the port works enter *IDN?. This command will return
information on the calibrator.

6.3 Changing Between Remote and Local Operation

There are three modes of operation of the calibrator, Local, Remote,
and Remote with Lockout. Local mode is the default mode.
Commands may be entered using the keypad on the calibrator or
using a computer. In Remote mode the keypad is disabled, and
commands may only be entered using a computer, but choosing
[GO TO LOCAL] from the menu on the calibrator display will restore
keypad operation. In Remote with Lockout, the keypad can not be
used at all. To switch modes proceed as follows:

1. To enable Remote mode, type in the serial command REMOTE
at the computer terminal.

2. To enable Remote with Lockout, type in “REMOTE LOCKOUT” in
either order.

3. To switch back to local operation enter LOCAL at the terminal.
This command also turns off LOCKOUT if it was on. For more
information on commands refer to the Remote Commands
section.

27

27

6.4 Using Commands

6.4.1 Command types

Refer to the Section 10.5 on Remote Commands for all available
commands.

The calibrator may be controlled using commands and queries. All

commands may be entered using upper or lower case. The
commands are divided into the following categories:

Calibrator Commands

Only the calibrator uses these commands. For example

VAL?

asks for the values displayed on the calibrator display.

Common Commands

Standard commands used by most devices. These commands
always begin with an “*”. For example

*IDN?

tells the calibrator to return its identification.

Query Commands

Commands that ask for information, they always end with a “?”. For
example:

FUNC?

Returns the current modes of the calibrator displays.

Compound Commands

Commands that contain more than one command on one line. For
example;

PRES_UNIT LOWER, PSI;PRES_UNIT?

Sets the presuure unit to PSI on the lower display to and queries it

to verify. In this case it will return the pressure units of all three dis­plays :

BAR,BAR,PSI

6.4.2 Character Processing

The data entered into the calibrator is processed as follows:

• ASCII characters are discarded if their decimal equivalent is less

than 32 (space), except 10 (LF) and 13 (CR):

2828

• Data is taken as 7-bit ASCII

• The most significant data bit is ignored.

• Upper or lower case is acceptable.

6.4.3 Response Data Types

The data returned by the calibrator can be divided into four types:

Integer

For most computers and controllers they are decimal numbers
ranging from -32768 to 32768. For example:

FAULT? could return 110

Refer to the Error Codes table (Table 8) for more information on error
codes.

Floating

Floating numbers have up to 15 significant figures and exponents.
For example:

VAL? returns 5.830000E01,PSI,0.000000E00,PSI,0.000000E+00,A

Character Response Data (CRD)

Data returned as keywords. For example:

PRES_UNIT? returns BAR,BAR,PSI

Indefinite ASCII (IAD)

Any ASCII characters followed by a terminator. For example:

*IDN? returns MARTEL, DPC-300A, 250, 1.00

6.4.4 Calibrator Status

Error Queue

If an error occurs due to invalid input or buffer overflow, its error

code is sent to the error queue. The error code can be read from the
queue with the command FAULT?. The error queue holds 15 error
codes. When it is empty, FAULT? returns 0. The error queue is

cleared when power is reset or when the clear command *CLS is
entered.

Input Buffer

Calibrator stores all received data in the input buffer. The buffer holds
250 characters. The characters are processed on a first in, first out
basis.

29

29

6.5 Remote Commands and Error Codes

The following tables list all commands, and their descriptions, that
are accepted by the calibrator.

Table 5: Common Commands

Command Description

*CLS (Clear status.) Clears the error queue.

*IDN? Identification query. Returns the manufacturer, model num-

ber, and firmware revision level of the Calibrator.

*RST Resets the calibrator to the power up state.

Table 6: Calibrator Commands

Command Description

DAMP Turns Damp on or off.

DAMP? Returns if DAMP is on/off

DISPLAY Turns on/off the displays specified in the command

DISPLAY? Returns which displays are on/off

ERROR_LOOP Turns loop power on or off in percent error mode

ERROR_LOOP? Returns the current state of loop power in error mode

ERROR_MODE Turns percent error mode on or off

ERROR_MODE? Returns whether percent error mode is on or off

ERROR_PORT Set the pressure port for percent error mode

ERROR_PORT? Returns the pressure port for percent error mode

FAULT? Returns the most recent error code

FUNC Sets the display mode as specified in the command

FUNC? Returns the current mode of the upper, middle, and lower

display

HART_ON Turns the hart resistor on.

HART_OFF Turns the hart resistor off.

HART? Returns the current state of the Hart resistor.

HI_ERR Sets the 100% of span limit for percent error mode

HI_ERR? Returns the 100% of span limit for percent error mode

IO_STATE Set the calibrator's mA state.

IO_STATE? Return the calibrator's mA state.

LOCAL Returns user to manual operation of the calibrator

30

30

LOCKOUT Locks out the keypad of the calibrator in remote operation

LO_ERR Sets the 0% of span limit for percent error mode

LO_ERR Returns the 0% of span limit for percent error mode

MOTOR_ON Turns the motor on.

MOTOR_OFF Turns the motor off.

MOTOR? Returns the current state of the Hart resistor

OUT Set the calibrator to output the requested current.

OUT? Returns the value of the current being simulated.

PRES_UNIT Set the pressure unit for the indicated display

PRES_UNIT? Returns the pressure from the indicated display

PUMP_LIMIT Sets the approximate value at which the pump will turn off.

PUMP_LIMIT? Returns the approximate value at which the pump will turn

off.

REMOTE Puts the calibrator in remote mode

SIM Set the calibrator to simulate the requested current.

SIM? Returns the value of the current being simulated.

ST_CLOSE? Returns pressure value at which the switch closed

ST_DEAD? Returns pressure value of the deadband of the switch

ST_OPEN? Returns pressure value at which the switch opened

ST_START Starts a switch test

VAL? Returns the measured values

ZERO_MEAS Zeros the pressure module

ZERO_MEAS? Returns the zero offset of the pressure module

Table 7: Parameter units

Units Meaning

DCI Current function

DCV Voltage measure function

EXT External pressure measurement function

LOWER Designates Lower display

MA Milliamps of current

MEASURE Measure state

MEAS_LOOP Measure with loop power state

MIDDLE Designates Middle display

PCT_ERR Percent Error

31

31

PERCENT Percent

P1 P1 pressure measurement function

ST_P1 Switchtest mode with P1

ST_EXT Switchtest mode with external module

SOURCE Source state

SIM Simulate state

UPPER Designates Upper display

V Voltage

Table 8: Error Codes

Error Number Error Description

100 A non-numeric entry was received where it should be a

numeric entry

101 Too many digits entered

102 Invalid units or parameter value received

103 Entry is above the upper limit of the allowable range

104 Entry is below the lower limit of the allowable range

105 A required command parameter was missing

106 An invalid command parameter was received

107 Pressure not selected

108 Invalid sensor type

109 Pressure module not connected

110 An unknown command was received

111 Bad Parameter received

112 The serial input buffer overflowed

113 Too many entries in the command line

114 The serial output buffer overflowed

6.6 Entering Commands

Commands for the calibrator may be entered in upper or lower case.

There is at least one space required between the command and

parameter, all other spaces are optional. Almost all commands for

the calibrator are sequential; any overlapped commands will be

indicated as such. This section will briefly explain each of the
commands and describe their general use, which will include any
parameters that may be entered with the command as well as what
the output of the command is.

32

32

6.6.1 Common Commands

*CLS

Clears the error queue. Also terminates all pending operations.

When writing programs, use before each procedure to avoid buffer
overflow.

*IDN?

Returns the manufacturer, model number, and firmware revision of
the Calibrator. For example:

*IDN? will return MARTEL, DPC300A, 0, 1.00

6.6.2 Calibrator Commands

DAMP

Turns the dampening function on or off.

For example:

If you send DAMP ON this will turn the dampening function

on.

DAMP?

Returns the current state of the dampening function.

For example:

If you send DAMP? It will return ON if the dampening

function is on.

DISPLAY

Turns the indicated display on or off.

For example:

If you send DISPLAY LOWER, ON this will turn the lower

display on.

DISPLAY?

Returns the current state of the each of the displays.

For example:

If you send DISPLAY? It will return ON, ON, ON if the all

the displays are on.

FAULT?

Returns the error code number of an error that has occurred.

The command may be entered when the previous command did
not do what it was meant to do.

33

33

For example, if a value for current output is entered that is bigger

than the supported range (0-24mA) FAULT? Would return:

103 which is the code number for an entry over range.

Refer to the Error Codes table for more information on error

code numbers.

ERROR _LOOP

Turns loop power on or off in percent error mode.

For example:

To set loop power on send ERROR_LOOP ON.

ERROR _LOOP?

Returns the current state of loop power in percent error mode.

For example:

If you send ERROR_LOOP? It will return ON if loop power

is on in error mode.

ERROR_ MODE

Turns percent error mode on and off.

For example:

To turn on percent error mode send ERROR_MODE ON.

ERROR _ MODE?

Returns the current state of percent error mode.

For example:

If you send ERROR_MODE? It will return ON if the

calibrator is in percent error mode.

ERROR_ PORT

Sets the pressure port for percent error.

For example:

To set the pressure port for percent error to [P1] send

ERROR_ PORT P1.

3434

ERROR _ PORT?

Returns the current pressure port for percent error mode.

For example:

If you send ERROR _PORT?, it will return P1 if the pressure

port in percent error is [P1].

FUNC

Sets the display indicated in argument one to the function

indicated in argument 2.

For example:

To set the lower display to pressure mode send FUNC

LOWER,[P1].

FUNC?

Returns the current mode of all displays. For example if the

calibrator is set to [P2] ST on the upper display, [P1] on the
middle, and [P1] on the lower, FUNC? Would return:

ST_P2,P1,[P1]

HART_ON

Turns the Hart resistor on.

HART_OFF

Turns the Hart resistor off.

HART?

Returns the state of the Hart resistor.

For example:

If the Hart resistor was on HART? Would return ON.

HI_ERR

Sets the 100% point for the percent error mode calculation in the

current engineering units.

For example:

To set the 100% point to 100 psi send HI_ERR 100.

35

HI_ERR?

Returns the 100% point for the percent error mode calculation.

For example:

If the 100% point is set to 100 psi, HI_ERR? would return

1.000000E+02, PSI .

IO_STATE

Sets the input/output/simulate state of the mA function of the

calibrator. Does not put the calibrator in mA if it is not in it
already.

For example:

If the calibrator is in mA simulate mode sending IO_

STATE MEASURE would put it in measure mode.

IO_STATE?

Returns the input/output/simulate state of the mA function of the

calibrator.

For example:

If the calibrator was in mA simulate mode IO_STATE?

Would return SIM.

LOCAL

Restores the calibrator to local operation if it was in remote

mode. Also clears LOCKOUT if the calibrator was in lockout
mode.

LOCKOUT

Sending this command sets the lockout state, when the unit is in

REMOTE or goes to remote it prohibits use of the keypad
completely. The lockout state can only be cleared by sending
the LOCAL command.

LO_ERR

Sets the 0% point for the percent error mode calculation in the

current engineering units.

For example:

To set the 0% point to 20 psi send LO_ERR 20.

36

LO_ERR?

Returns the 0% point for the percent error mode calculation.

For example:

If the 0% point is set to 20 psi, LO_ERR? would return

2.000000E+01, PSI .

MOTOR_ON

Turns the motor on.

MOTOR_OFF

Turns the motor off.

MOTOR?

Returns the state of the motor.

For example:

If the motor was on MOTOR? Would return ON.

OUT

This command also switches the calibrator into mA output

mode. A number and a unit must be entered after the command.

For example:

OUT 5 MA sets the current output at 5 mA

OUT?

Returns the output of the calibrator.

Using the above example, OUT? Would return: 5.000000E-03, A

PRES_UNIT

Used to set the pressure unit for the indicated display

For example:

To set the pressure unit to psi on the lower display send

PRES_UNIT LOWER, PSI.

PRES_UNIT?

Returns the pressure unit used when measuring pressure for

each of the 3 displays.

37

PUMP_LIMIT

Sets the approximate pressure in psi at which the pump will turn

off.

For example:

PUMP_LIMIT 50 sets the approximate value that the pump

will shutoff at to 50 psi

PUMP_LIMIT?

Returns the pump limit. Using the above example, PUMP_LIMIT?

Would return:

50.000

REMOTE

Puts the calibrator in remote mode. From the remote mode the

user can still use the keypad to get back to local unless the
command LOCKOUT was entered before REMOTE. Then the
keypad is totally locked out, and the user has to send the LOCAL
command to get back to local operation.

SIM

Sets the output for current simulation. This command also

switches the calibrator into mA simulation mode. A number and
a unit must be entered after the command.

For example:

SIM 5 MA sets the current simulation at 5 mA

SIM?

Returns the output of the current simulation. With the example

above, the output would be: 5.000000E-03, A

ST_START

Starts a switch test.

ST_CLOSE?

Returns the pressure that the switch closed at in the current

pressure units.

38

ST_OPEN?

Returns the pressure that the switch opened at in the current

pressure units.

ST_DEAD?

Returns deadband of the switch in the current pressure units.

VAL?

Returns the value of any measurement taking place on the upper

and lower display. For example, if the upper display is measuring
5mA, and the lower display is measuring 10V, then VAL? will
return:

5.000000E-03, A, 1.000000E+01, V

ZERO_MEAS

Zeroes the attached pressure module. Enter the zeroing value in

PSI after the command when zeroing an absolute pressure
module.

ZERO_MEAS?

Returns the zero offset or the reference value for absolute

pressure modules.

39

7. Specifications (15 °C to 35 °C unless otherwise noted.)

General

Instrument Setup Recall 5; last used on power-up

Environmental

Operating Temperature

Storage Temperature

Battery Type DC 16V, NiMH rechargeable battery

Battery Life (fully-charged) Approx. 50 hours (only measurement or with

Physical

Dimensions

Weight

EMI/RFI Conformance EN50082-1: 1992 and EN55022: 1994 Class B

Safety EN/IEC 61010-1:2010 3rd Edition (Low Voltage

Connectors/Ports 1/8” NPT BetaPort-P pressure module adapter;

Included Accessories manual, NIST-traceable certificate, test leads

-10 °C to +50 °C

-20 °C to +60 °C

external pressure supply)
125 pump cycles to 20 bar
300 pump cycles to 10 bar
1,000 pump cycles to 2 bar

15.25" x 12: x 7" (387.4 x 304.8 x 177.8 mm)

15.5 lbs. (approx. 7 kg)

Directive)

and hose kit.

Ranges

Pressure -12 to 300.00 psi

mA 0 to 24.000 mA

Volts 0 to 30.000 VDC

Engineering Units psi, bar, mbar, kPa, MPa, kgcm2, mmH

4°C, mmH2O @ 20°C, cmH2O @ 4°C, cmH2O
@ 20°C, inH
60°F, mmHg @ 0°C, inHg @ 0°C

O @ 4°C, inH2O @ 20°C, inH2O @

2

Accuracy

Pressure ±0.025% of rdg ±0.01% of F.S.

mA ±0.015% of rdg ±0.002mA

Volts ±0.015% of reading ±0.002V

Temperature Effect (all functions)

No effect on accuracy on all functions from 15°C to 35°C

Add ±0.002% F.S./°C for temps outside of 15°C to 35°C

40

O @

2

8. Warranty

Martel Electronics Corporation warrants all products against material
defects and workmanship for a period of twelve (12) months after the
date of shipment. Problems or defects that arise from misuse or
abuse of the instrument are not covered. If any product is to be
returned, a “Return Material Author ization” form can be obtained
from our website www.martelcorp.com under customer service. You
can also call 1-800-821-0023 to have a form faxed. Martel will not be
responsible for damage as a result of poor return packaging. Out of
warranty repairs and recalibration will be subject to specific charges.
Under no circumstances will Martel Electronics be liable for any
device or circumstance beyond the value of the product.

9. Maintenance

9.1 Cleaning the Unit

Warning

To avoid personal injury or damage to the calibrator, use only the
specified replacement parts and do not allow water into the case.

Caution

To avoid damaging the plastic, do not use solvents or abrasive
cleansers.

Clean the calibratwith a soft cloth dampened with water or water and
mild soap.

9.2 Service Center Calibration or Repair

Only qualified service personnel should perform calibration, repairs,

or servicing not covered in this manual. If the calibrator fails, check
the batteries first, and replace them if needed.

Verify that the calibrator is being operated as explained in this
manual. If the calibrator is faulty, call for an RMA number or go to
www.martelcorp.com to download an RMA form to return the unit. Be
sure to pack the calibrator securely, using the original shipping
container if it is available.

41

Ranges and Resolutions

Range (PSI) 300 PSI / 20 Bar

Burst Pressure (PSI) 2000

Proof Pressure (PSI) 600

Engineering Unit Factor

Psi 1 300.00

bar 0.06894757 20.684

mbar 68.94757 20684

kPa 6.894757 2068.4

MPa .00689476 2.0684

kg/cm2 0.07030697 21.092

cmH2O @ 4°C 70.3089 21093

cmH2O @ 20°C 70.4336 21130

mmH2O @ 4 °C 703.089 N/A

mmH2O @ 20°C 704.336 N/A

inH2O @ 4°C 27.68067 8304.2

inH2O @ 20°C 27.72977 8318.9

inH2O @ 60°F 27.70759 8312.3

mmHg @ 0°C 51.71508 15515

inHg @ 0°C 2.03602 610.81

• Proof pressure - maximum allowable pressure without a shift in calibration

• Burst pressure - sensor damaged or destroyed; some risk of personnel injury

• Absolute ranges - the data for the 30 PSI / 2.0 Bar, 150 PSI / 10 Bar and 300

PSI / 20 Bar ranges also applies to the absolute pressure versions of those
ranges.

42

0220022 Rev B 4/13

www.martelcorp.com

e-mail: [e-mail]

Tel: [phone]

Fax: [phone]

Martel Electronics
3 Corporate Park Dr.

Derry, NH 03038