
AMETEK JOFRA APC
Advanced Pressure Calibrator
Reference Manual

1. Introduction
The Ametek APC is a high accuracy, full function pressure calibrator. The
calibrator includes the following features and functions:
• Dual display. The upper portion of the display is used to read pressure in
various units. The lower portion of the display is primarily used to read
current (up to 24 mA).
• Pressure can be read from an internal sensor or an external module (APM).
• Switch test functionality uses an higher speed pressure update rate for
superior performance.
• Current can be read with or without loop power.
• An RS232 interface allows complete “hands off” remote control monitoring.
The Ametek APC is well suited for various applications including calibration of
gauges, pressure switches, safety valves, and P/I transmitters.
The APC is available in the following ranges:
10 psi / 0.7 bar 1,000 psi / 70 bar
30 psi / 2 bar 3,000 psi / 200 bar
200 psi / 15 bar 5,000 psi / 350 bar
500 psi / 35 bar 10,000 psi / 700 bar
Vacuum is supported in all units up to 500 psi / 35 bar.
External pressure modules (APMs) can be added to support additional
pressure ranges.
Read this manual carefully before using the instrument and make
sure that all safety instructions and warnings are observed.
1.1 Contacting Ametek
US, Canada, Latin America AMETEK TCI at 1-800-527-9999
Europe, Africa, Middle East AMETEK Denmark A/S at + 45 4816 8000
Asia AMETEK Singapore Pte. Ltd. at
+ 65 (64) 842 388
1.2 Standard Equipment
Inspect the unit carefully upon receipt. Save packing carton in case reshipment is necessary. If there appears to be any damage, equipment missing
or if there are any questions about the unit, contact AMETEK.
Check to see if your calibrator is complete. It should include:
• APC Calibrator
• Instruction Manual
• Test Leads
• Carrying Case
• (2) Pressure Fittings
• Calibration Certificate
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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
Crossed out wheeled bin (comprehended by the directive 2002/95/EC)
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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.
• Thermostats must not be connected to any other voltage source during
a test
• 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 using a pressure module, make sure the process pressure line is
shut off and depressurized before you connect it or disconnect it from
the APC or pressure module.
• Disconnect test leads before changing to another measure or source
function.
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• 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.
• 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 possible damage to calibrator or to equipment under test:
• Disconnect the power and discharge all high-voltage capacitors before
testing resistance or continuity.
• Use the proper jacks, function, and range for your measurement or
sourcing application.
• If the message changes to "OL" the range limit is exceeded and the
pressure source must immediately be removed from the APC to prevent
damage to the pressure transducer inside.
• Maximum torque allowed is 15Nm/10 ftlbs. NEVER exceed the torque
allowed.
• To avoid damaging the plastic lens and case, do not use solvents or
abrasive cleansers.
Clean the calibrator with a soft cloth dampened with water or water and
mild soap.
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2. Calibrator Interface
2.1 Display and Inputs
The calibrator display has two numeric character lines. The large line
shows the measured pressure, and the small line shows the measured
current. The measured current may be displayed in mA, in percentage of
mA range (4mA - 20mA), where 0% corresponds to 4mA and 100% to
20mA, or percent error (see section 4.3). Pressure units are located on the
right side of the display. For a listing of all the units supported refer to the
table in the Specifications section.
The calibrator has two sets of input terminals located on top of the unit and
a pressure fitting located on the bottom of the unit. The input terminals on
the right are used for measuring current. The terminals on the left are used
for pressure switch connection.
2.2 Key Functions
Figure 1 shows the layout of the calibrator keypad while Table 1 lists the
individual keys and their functions.
Table 1: Key Functions
Key Function
1 Turns the unit on and off
2 Select different pressure units. Press and hold while unit is powering up to
change the power saver setting. Also used for % error data entry.
3 Switches the lower numeric display between mA, percentage of range and
% error function. This key also enables loop power when held during
power up.
4 Zeroes the pressure sensor. Also acts as enter key in the % error mode.
5 Used in Switch Test mode (see section 5)
6 Displays the minimum and maximum pressure and current measured since
power up. Also used for % Error data entry

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Figure 1
2.3 Power Saver
The calibrator has an adjustable power saver option that allows it to shut
down after being idle (no keys pressed) for a period of 1 to 30 minutes. To
set the shutoff time:
1. Press and hold the (UNITS) key while powering up the unit.
2. A number from 1 to 30 or OFF will appear on the bottom of the display.
3. Use the (UNITS) key to increase the number, and the (MAX/MIN) key to
decrease the number.
4. To disable power saver mode decrease the number until OFF is
displayed on the screen.
5. Press the (ZERO) key to save the settings and return to normal
operation.

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3. Measuring Pressure and Current
Warning
Make sure the process pressure line is shut off and depressurized before
you connect it or disconnect it from the APC or pressure module.
Caution
• If the message changes to "OL" the range limit is exceeded and the
pressure source must immediately be removed from the APC to prevent
damage to the pressure transducer inside.
• Maximum torque allowed is 15Nm/xx ftlbs. NEVER exceed the torque
allowed.
To measure pressure, connect the calibrator using an appropriate fitting.
Choose a pressure unit for measurement with the (UNITS) key. Pressure will
be displayed on the large numeric display. Use the (ZERO) key to zero the
pressure sensor when vented to atmospheric pressure
Important NOTE: To ensure accuracy of the calibrator it is critical to zero
the APC before a device is calibrated.
To measure current use the mA input terminals on the top of the calibrator.
Current can be measured in mA or percentage of range. The range on the
calibrator is set to 0% at 4 mA and 100% at 20 mA. For for example if the
current measured is displayed as 75% then the mA value is 16 mA.
3.1 Media Compatibility
The APC calibrator utilizes a media isolated sensor to prevent sensor
contamination. Whenever possible clean, dry air is the media of choice. If
that is not always possible, make sure that the media is compatible with
the following wetted parts:
Low Pressure - Unit range up to 200 PSI High Pressure - Unit range 500
PSI and up
1) Nickel plated brass 1) 316 Stainless Steel
2) Glass
3) RTV (silicone)
4) BUNA-N
3.2 Measuring Pressure with External Modules (APMs)
The APC provides a digital interface to External Pressure Modules (APMs).
These modules are available in various ranges and types including gauge,
vacuum, differential and absolute. The modules work seamlessly with the
calibrator. Simply plug them in to the interface and the reading from the
internal sensor will be replaced by that of the APM. Since the interface