Teledyne HASTINGS 2002 User manual

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MODEL 2002
VACUUM GAUGE
HASTINGS
INSTRUCTION
MANUAL

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Manual Print History
The print history shown below lists the printing dates of all revisions and addenda created for this
manual.The revision level letter increases alphabetically as the manual undergoes subsequent
updates.Addenda, which are released between revisions, contain important change information that
the user should incorporate immediately into the manual.Addenda are numbered sequentially.
When a new revision is created, all addenda associated with the previous revision of the manual are
incorporated into the new revision of the manual. Each new revision includes a revised copy of this
print history page.
Revision A (Document Number 149-0798) ...........................................................September 1998
Hastings Instruments reserves the right to change or modify the design of its equipment without
any obligation to provide notification of change or intent to change.

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Table of Contents
1.0 GENERAL INFORMATION.............................................................. 5
1.1 Features ................................................................................................................................5
1.2 Model 2002 Sensors ............................................................................................................. 5
1.3 Model 2002 Control Unit......................................................................................................6
1.4 Specifications ........................................................................................................................ 6
2.0 INSTALLATION .................................................................................. 7
2.1 Receiving Inspection ............................................................................................................. 7
2.2 Quick Start ............................................................................................................................ 7
2.3 Transducer Installation .......................................................................................................... 7
2.4 Control Unit Installation ........................................................................................................ 8
2.5 Initial Operation .................................................................................................................... 8
3.0 FRONT PANEL OPERATION ........................................................... 9
3.1 Overall Functional Description .............................................................................................. 9
3.2 RUN Mode ......................................................................................................................... 10
3.3 HI and LOW Set Point Modes ............................................................................................ 11
3.4 CAL Mode ......................................................................................................................... 11
3.5 GAS Mode ......................................................................................................................... 13
3.6 UNITS Mode ..................................................................................................................... 14
4.0 REAR PANEL DESCRIPTION....................................................... 1 5
4.1 Remote Zero Input ............................................................................................................ 15
4.2 Analog Output .................................................................................................................... 15
4.3 TTL Outputs ...................................................................................................................... 15
4.4 Power Entry Module...........................................................................................................16
5.0 THEORY OF OPERATION ............................................................. 1 9
5.1 Piezoresistive Sensor ........................................................................................................... 19
5.2 Pirani Sensor ....................................................................................................................... 21
5.3 Dual Sensor Operation ....................................................................................................... 24
6.0 RS-232 OPTION BOARD................................................................ 2 7
6.1 RS-232-E Interface Specifications ....................................................................................... 27
6.2 Interface Connector Pin Assignments .................................................................................. 27
6.3 Operation of the Serial Interface ......................................................................................... 28
6.4 Installation of the RS-232 Board ......................................................................................... 31

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7.0 RELAY INTERFACE OPTION BOARD...................................... 3 3
7.1 Relay Board Specifications .................................................................................................33
7.2 Terminal Strip Connections ................................................................................................ 33
7.3 Operation ...........................................................................................................................34
7.4 Relay Board Installation .....................................................................................................34
8.0 TROUBLESHOOTING GUIDE .................................................... 3 5
9.0 WARRANTY AND REPAIR ........................................................... 3 7
9.1 Warranty Policy ..................................................................................................................37
9.2 Non-Warranty Repair Policy .............................................................................................. 37
10.0 DIAGRAMS AND DRAWINGS .................................................... 3 9

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General Information
SECTION 1
The Model 2002 is a wide range vacuum measuring instrument consisting of a digital microproces-
sor-based display unit, a miniature, rugged, thin film based sensing element that measures from
below 1x10-4 Torr up to 100 Torr with its matched EEPROM (Electrically Erasable/Programmable
Read Only Memory), a piezoresistive sensor that measures from 1 to 1000 Torr, and an intercon-
necting cable. Together, these components provide accurate vacuum measurement over 7 decades
of vacuum from 1x10-4 Torr to 1000 Torr. This instrument is a new design approach based on
over 50 years of experience by Hastings Instruments with well-known and widely used thermal
conduction vacuum measurement techniques. The Model 2002 is designed for quick,easy installa-
tion and will provide the user with long lasting, trouble free, accurate vacuum measurement.
1.1 Features
 Wide dynamic range: 1x10-4 to 1000 Torr
 Compact rugged design
 Attitude insensitive
 Fast dynamic response
 Withstands 150 psig positive pressure
 Linear per decade
 Bakeable to 2500C
 TTL output process control
 Interchangeable transducer
 Corrosion resistant
1.2 Model 2002 Sensors
The Model 2002 transducer is comprised of an ion implanted, piezoresistive, direct force sensor
and a thin film Pirani type sensor. The Pirani sensing element is a Pt thin film serpentine element
(see Figure 5.3a) deposited on a 1 micron thick Si3N4 membrane. The membrane is peripherally
supported by a Si box shaped die and is covered by a thick Si lid parallel to the membrane and
open on two ends (see Figure 5.3b). The piezoresistive unit is an ion implantedWheatstone bridge
in a 1 micron thick Si membrane peripherally supported by a Si box shaped die which has been
anodically bonded to a Pyrex substrate.
The dual sensor assembly is encased in a corrosion resistant 316 stainless steel tube shell. The
durable tube design withstands high pressure (150 psig/10.2bar), and high pressure surges. Since
the Pirani sensor is miniaturized and employs a Pt thin film on a Si3N4membrane (instead of a
conventional long fragile wire), the transducer can withstand high levels of mechanical shock.
The Model 2002 is designed for fast response. The micromachined sensing elements have a very
small mass and operate in a constant temperature (Pirani) and a constant current (piezo) feedback
mode. This makes response time very fast as compared to other commercially available sensors
which have to change the temperature of a significant mass to reflect pressure changes and have a
large internal volume which must equalize in pressure before the sensor can reach its final value.
Also,the transducers small internal volume (<1.5cc) permits rapid pneumatic response to system
pressure changes. Further, the small geometry of the transducer prevents thermal convection
currents which allows the sensor to be mounted in any orientation without calibration shifts.

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1.3 Model 2002 Control Unit
The Model 2002 control unit consists of the power supply, Pirani resistance bridge control, signal pro-
cessing and display circuitry. The user interface consists of a flat panel display with smooth operating
tactile switches and large green LED digits (0.56"/14.2mm). The pressure is displayed in scientific format
using a 3 digit mantissa and a 1 digit (plus sign) exponent. The pressure can be displayed in Torr,mbar, or
Pascal (optional). The instrument comes standard with 2 alarm setpoints that have TTL level digital
outputs. An optional dual relay board can be internally mounted to trip on the alarm setpoints to turn on/
off various equipment such as pumps, valves, heaters, bakeout ovens, and safety equipment. The Model
2002 instrument accepts an external TTL level "Remote Zero" to zero the instrument when another
instrument (e.g. an ion gauge) indicates that the pressure is less than 1x10-5 Torr. The analog output is
linear per decade directly corresponding to the control units display. The Model 2002 comes calibrated
for nitrogen. Conversion factors for other gases are selectable by the user (see section 3.6). This direct
readout display allows for flexibility in user system configurations which operate with various gases.
An optional serial interface board can be installed to provide RS232 or RS485 support. The Model 2002
control unit fits a standard DIN 43700 insert (1/4 DIN) and mounts into a 3.62 in. (92 mm) square hole.
The case is constructed of NORYL rated UL-94-V1 (self-extinguishing plastic) and is equipped with
mounting brackets that are adjustable up to 3/16 (4.8mm). The control unit case can be configured to be
NEMA 12 compliant.
1.4 Specifications
Measuring range ....................................................................................... 1x10-4 Torr to 10+3 To r r
1.3x10-4 mbar to 1.3x10+3 mbar
Accuracy (1x10-4 to 1x10+3 Torr) .................................................. + 15% of reading (N2,T=230C)
Ambient temperature operating range ..........................................................................00C to 500C
Bakeout temperature (with transducer electronics removed) ................................................. 2500C
Analog output .............................................................. 1.22-4.5 Volts (0.5VDC linear per decade)
Process control................................................................. 2TTL outputs (1TTL auto zero input)
Digital readout ............................................................... Four green LED - resolution is three digit
mantissa (plus exponent)
Power.................................................... 90-130 & 180-260VAC, 50 to 60 Hz IEC-320 receptacle.
A 6 ft., 3-wire power cord is provided with each unit.
Fuse ............................................................................................................................. 250V, 1/4 A.
Transducer mounting .................................................................. Any position without recalibration.
Transducer internal volume ...................................................................................................<1.5cc
Wetted material ....................................................................................... Au, Si3N4, Si, Pt, PyrexTM,
KovarTM and 316 stainless steel
Stability with voltage ..................................................................... Variation in reading undetectable
as power fluctuates within power specification.
Weight (display, cable, and sensor) ................................................ Net: 2.5 lbs., Shipping: 3.4 lbs.
Transducer response time .................................................... Typically less than 400 msec for a step
change from 10-3 Torr to 10+3 To r r .
Positive pressure................................................................................................................. 150 psig
NEMA rating ................................................................. 12 (with use of supplied mounting gasket)

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SECTION 2
Installation
This section is designed to assist in getting a new pressure gauge into operation as quickly and
easily as possible. Please read the following instructions thoroughly before installing the instrument.
2.1 Receiving Inspection
Carefully unpack the Hastings Model 2002 Instrument (part # HPM-2002), transducer (part
#HPM-2002s) and cable (part # CB 2000). Inspect all items for any obvious signs of damage due
to shipment. Immediately advise the carrier who delivered the shipment if any damage is suspected.
Compare each component shipped against the packing list. Ensure that all parts are present (i.e.
transducer, power supply, cables,etc.). In addition to the components listed on the packing list,the
shipment includes: AC power cord, panel mounting hardware, 7-pin circular DIN connector,and a
front-panel gasket for users needing a NEMA 12 rating. Optional equipment or accessories will be
listed separately on the packing list.
2.2 Quick Start
Follow this procedure to get your new Model 2000 vacuum gauge up and running.
1. Remove sensor from protective packaging.
2. Transducer tube may be installed in any orientation.However if condensation is likely to occur,
then the port should be orientated downward.
3. When installing 1/8 NPT style transducer tube, use the 7/16 wrench flats on the tube stem.
4. Connect transducer cable (orange) to controller .
5. Connect other end of transducer cable to transducer. A finger tight connection is adequate for
proper operation.
6. If you have computer interface or process control options, these cables can now be attached.
7. I/O port diagram is given in the manual.
8. Connect the AC power cord. The Model 2002 automatically adjusts for 90-245VAC 50/60 Hz.
9. Turn on power switch. Gauge is now reading pressure in units of Torr (default).
10. For best accuracy, the gauge should now be zeroed. Pump the vacuum system down to low
10-6 Torr (if possible). Ideally the gauge should be operated in this condition for one hour.
11. Place the Model 2002 in the CAL mode by using the mode button. Press the up and down
arrows simultaneously (CAL light is now flashing).
12. Press the ZERO button once and return to the RUN mode using the mode button.
The gauge is now ready for normal operation and the display is a true indication of the system
pressure.
2.3 Transducer Installation
The Model 2002 transducer is shipped with a protective plastic cap which keeps dust out of the
tube. This cap must be removed prior to installation. The transducer may be installed in any
orientation. Although the transducer is rugged and will perform well in many harsh environments,
the tube should be installed in a clean and careful manner. The tube is configured with the vacuum
fitting requested. If your molecular sieve vacuum environment is highly contaminated or has
unique fitting requirements, a Hastings filter or special adapter may be needed. Please contact the
Hastings Instruments Sales Department for assistance in your system configuration.

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2.4 Control Unit Installation
Environment:
The instrument can be operated over a temperature range of 0oC to 50oC. The instrument case
can be in NEMA 12 compliance (i.e. a reasonable degree of protection against dust and dripping
noncorrosive liquids in a panel configuration) with the front panel gasket installed. To install, slide
the gasket over the back of the control unit prior to panel mounting (panel mount Instructions on
page 6).Also refer to panel mounting detail on page 43.
NOTE: Back panel is not sealed.
Panel Mount Instructions:
The control unit can be panel mounted. See detail on page 43. The hole dimensions on the panel
are 3.62" x 3.62"(92.8mm x 92.8 mm). Slide the neoprene gasket that was shipped with the control
unit onto the case from the back. Slide the controller through the panel cutout. Hold the hardware
against the side and tighten the two screws.
Transducer Cable Attachment:
The threaded connector attaches to the transducer. A finger tight connection is adequate for
proper operation. The 8-pin circular DIN connector attaches to the back panel (See Figure 4.1).
The transducer cable connects to the left hand connector when looking at the back. The transducer
cable cannot connect to the I/O DIN connector but the seven pin I/O cable could be mistakenly
connected to the eight pin sensor connector. Ensure that the seven pin I/O cable is plugged into the
proper position.
I/O Cable Attachment:
The mating male plug to the I/O connector is supplied with the unit. An I/O cable can be wired
with the 7-pin circular DIN connector to use the analog output, digital alarms or the remote zero
functions.The connector will accept 20 gauge or smaller wire.The pinout is shown in Figure 2.1
(back panel figure). A detailed description of these pins is given in Section 4.
NOTE: It is recommended that the male plug be plugged into the female socket before
attempting to solder wires to the plug since this will keep the heat from deforming the
plug.
2.5 Initial Operation
Upon applying power to the control unit a pressure measurement will be given in Torr for nitrogen.
However, it is recommended that the user follow the instructions for zeroing and adjusting the
output at atmospheric pressure in Section 3.4 ("Cal Mode").

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Front Panel Operation
SECTION 3
3.1 Overall Functional Description
The front panel of the control unit is shown in Figure 3.1. The four circular blue buttons are used
for the selection of display readout and the input of data. The green data field displays the data as
determined by mode selection. The MODE button toggles the control unit in a clockwise fashion
among the six modes of operation:
RUN Normal operation,pressure is displayed in scientific notation. The analog to digital
converter speed can be adjusted and the factory calibration can also be restored in this
mode. See Section 3.2 for further information.
HIGH High set point is displayed in scientific notation, above this pressure the HIGH TTL
output will be +5V.
LOW Low set point is displayed in scientific notation,below this pressure the LOW TTL
output will be +5V.
CAL. Pressure is displayed and can be adjusted.
GAS Gas number is displayed and selection may be changed.
UNITS Units used to display pressure are selected.
In the RUN, HIGH, and LOW modes, it is possible to see the display indicate that the data is out
of range. Overrange is indicated by . x10-. Underrange is indicated by 0.0 x10-. A mea-
sured pressure between 0 and 1x10-4 Torr is indicated by 0.0 x10+.
Model 2002 Control Unit Front Panel Figure 3.1
UPARROW
DOWN
ARROW
MODE BUTTON ZERO BUTTON
mbar
Torr
Pa
HASTINGS INSTRUMENTS
DUAL SENSOR VACUUM GAUGE
MODEL 2002

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Scientific Notation
The Model 2002 measures pressure spanning more than seven decades.In order to easily display
these readings, Hastings Instruments has employed scientific notation. In scientific notation, the
mantissa (the fixed point part) is multiplied by some power of 10 (given by the exponent).
Powers of 10
103= 1000 10-1 = 0.1
102= 100 10-2 = 0.01
101= 10 10-3 = 0.001
100= 1 10-4 = 0.0001
As an example: 7.60 x 10+2 To r r
mantissa exponent
"7.60 multiplied by 100" = 760Torr which is one atmosphere of pressure.
3.2 Run Mode
Normal Operation
The Model 2002 will automatically enter RUN mode upon start-up. This is the mode for normal
operation and the mode in which the instrument will typically spend most of its time. In the run
mode the Model 2002 unit will continuously monitor the pressure and update the alarm conditions
at the speed of the A/D converter and will update the display about four times per second.
A/D Speed Adjust
The Model 2002 utilizes a 24 bit sigma-delta analog to digital converter. This type of converter
averages the input over time to reject interference. Longer averaging times result in more accurate
readings. Increasing the A/D speed will respond to sudden pressure changes faster.
While in the RUN mode, the user can adjust the A/D speed of operation from about 10 Hz to 1000
Hz.At start-up,the instrument will be operating with an A/D frequency of about 60 Hz. The speed
can be adjusted two steps faster.Each step will increase or decrease the A/D frequency by a factor
of two.
In RUN mode, pushing the up arrow will speed up the A/D converter one step and decrease the
response time until the limit is reached (3 steps max). Pressing the button after the limit is reached
has no effect. There will be no indication of the operating speed other than the least significant
digits of the display will tend to run at higher speeds. This will result in a faster triggering of alarms
or relays if a sudden catastrophic failure occurs.
Pushing the down arrow will slow down the A/D converter and increase its accuracy. This will
improve the ability to resolve low pressure readings. If a certain speed is desired, press the up or
down arrows three times and then press the other arrow to select the other speed.
EEPROM Calibration Restoration
There are interlocks built into the CAL mode to minimize the chance of accidental alteration of the
calibration coefficients,but if calibration alteration does occur, the EEPROM calibration data can be
restored in the RUN mode by pressing the up and down arrows simultaneously (Run light will
flash), then press the ZERO button, up and down arrow buttons simultaneously. To permanently
restore the factory calibration, press the mode switch enough times to cycle through all of the
operating modes and back to RUN.
This will not correct the calibration if the tube has become contaminated or damaged.This reset
will not affect the gas selection, units or setpoints.
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