Kurt J. Lesker 979 Series User manual

Operation and
Maintenance Manual
Series 979 Atmosphere to
Vacuum Transducer

Series 979 ATVTransducer
Part # 100014438
Series 979 Atmosphere to
Vacuum Transducer

Series 979 ATVTransducer
Part # K____________________
Please fill in the transducer part and flange type numbers
in the space above and have them readily available when
calling for service or additional information.
(The part number can be found on your packing slip. Both
the part number and serial number are located on the
bottom side of the housing.)
For more information or literature, contact:
Kurt J. Lesker Company
1925 Route 51
Clairton, PA 15025-3681 USA
Phone: [phone]
1-800-245-1656
Fax: [phone]
©2003 by the Kurt J. Lesker Company, All rights reserved.

Series 979 ATVTransducer
Table of Contents
Package Contents ..................................................................... 9
Symbols Used in this Manual .................................................. 10
Safety Precautions .................................................................. 11
General Specifications ............................................................ 13
Feature and Control Locations ................................................ 14
About the 979 ATV Transducer ................................................ 15
Typical Applications for the 979 ATV Transducer ..................... 16
Installing the 979 ATV Transducer ........................................... 17
ATV Transducer Installation ....................................................................17
Location ...........................................................................................17
Orientation .......................................................................................17
Contamination ..................................................................................18
Vacuum Connection ............................................................................... 18
Electrical Connection .............................................................................19
Input/Output Wiring ..........................................................................19
979 ATV Transducer Electrical Connections Table ............................20
Relay Inductive Loads and Arc Suppression ..........................................20
Operation................................................................................. 22
979 ATV Transducer Factory Defaults Table ............................................22
RS-485 Protocol .....................................................................................23
Standard Addresses ........................................................................23
Universal Addresses ........................................................................23
Query and Command Syntax ...........................................................23
Response Syntax (ACK/NAK) .........................................................24
RS-485 Command Set ............................................................ 25
Set Up Commands ................................................................................. 25
Active Filament – AF .......................................................................25
Address – AD .................................................................................. 25
Baud Rate – BR ...............................................................................26
Emission Current – EC ....................................................................26
Factory Default – FD ........................................................................26
RS Delay – RSD ..............................................................................26
Test RS485 – TST ............................................................................ 27
Unit – U ............................................................................................27
User Tag – UT ..................................................................................27
Status Commands.................................................................................. 27
Device Type – DT .............................................................................27
Filament Status – FS .......................................................................28
Firmware Version MicroPirani – FV ..................................................28

Series 979 ATVTransducer
Firmware Version Hot Cathode – FVHC ........................................... 28
Hardware Version MicroPirani – HV ..................................................28
Hardware Version Hot Cathode – HVHC ........................................... 28
Model – MD .....................................................................................28
Serial Number – SN .........................................................................29
Time On – TIM1, TIM2 ..................................................................... 29
Transducer Status – T ...................................................................... 29
Transducer Temperature – TEM1, TEM2 ........................................... 29
Pressure Measurement and Degas Commands ...................................... 30
Filament Power – FP ........................................................................ 30
Degas Power – DG ........................................................................... 30
Pressure Reading – PR1, PR2, PR3 ................................................30
Set Point Commands ............................................................................. 31
Set Point Value – SP1, SP2, SP3 .................................................... 31
Hysteresis Value – SH1, SH2, SH3 ................................................. 31
Set Point Direction – SD1, SD2, SD3 ..............................................31
Enable Set Point – EN1, EN2, EN3 ................................................. 32
Enable Control Set Point – ENC ......................................................32
Set Point Status – SS1, SS2, SS3 ..................................................32
Protect Set Point – PRO .................................................................. 32
Calibration Commands ...........................................................................33
Atmospheric Calibration – ATM ........................................................33
Vacuum Calibration – VAC ...............................................................33
Gas Type Calibration – GT ............................................................... 33
Gas Correction – GC ........................................................................ 34
Degassing the Sensor ............................................................. 35
Sensitivities Relative to Nitrogen ............................................ 36
Gas Correction Factor Table ...................................................................36
Analog Output ......................................................................... 37
Pressure to Voltage Table .................................................................. 38-40
Leak Detection ........................................................................ 41
Bakeout/Sensor Replacement................................................. 42
Bakeout ..................................................................................................42
Sensor Replacement .............................................................................. 43
Maintenance and Troubleshooting .......................................... 44
Maintenance and Troubleshooting Table ..................................................44
Cleaning the 979 ATV Transducer Case and Sensor Tube ....................... 45
Sensor Test Resistance Values Table .....................................................46

Series 979 ATVTransducer
Accessories and Part Replacement ........................................ 47
Notes ....................................................................................... 48
Appendix: How the 979 ATV Transducer Works....................... 49
Hot Cathode Ionization Sensor ...............................................................49
Pirani Sensor.......................................................................................... 50
MicroPirani Sensor ................................................................................. 51

Series 979 ATVTransducer

Series 979 ATV Transducer 9
Before unpacking the 979 Atmoshpere to Vacuum (ATV) Transducer, check all
surfaces of the packing material for shipping damage.
Confirm that the 979 ATV Transducer package contains these items:
♦One 979 ATV unit (integrated sensor and electronics)
♦One 15-pin female D-sub connector kit
♦One 979 Atmosphere to Vacuum Transducer Operation and Maintenance
Manual
Inspect the components for visible evidence of damage during shipment. If
anything has been damaged, notify the carrier immediately. Keep all shipping
materials and packaging for claim verification.
If any items are missing from the package, call Kurt J. Lesker
Customer Service at 1-412-387-9200 or 1-800-245-1656.
Do not return the product to Kurt J. Lesker unless specified to do so by Kurt J.
Lesker Customer Service.
Kurt J. Lesker customer service and support:
Kurt J. Lesker Company Telephone [phone]
1925 Worthington Avenue Toll-Free 1-800-245-1656 (USA only)
Clairton, PA 15025 Facsimile 1-412-384-2745
USA
Package Contents

10 Series 979 ATV Transducer
CAUTION: Risk of electrical shock.
CAUTION: Refer to the manual. Failure to heed the message could
result in personal injury, serious damage to the equipment, or both.
Calls attention to important procedures, practices, or conditions.
Symbols Used in this Manual

Series 979 ATV Transducer 11
Safety Precautions
Always disconnect the power supply before removing
electronics from the Hot Cathode sensor for sensor replacement
or bakeout purposes. Lethal voltages and currents may be present
while the circuit is operating. Only a qualified technician should
replace or adjust electronic components.
Use the proper power source. Use + 24 VDC @ 0.75 Amps.
Properly ground the transducer. The transducer should be
connected to earth ground both through the vacuum flange and the
back shell of the electrical connector.
Do not turn on filament power when system pressure is above
5x10-2 Torr. Hot Cathode sensor damage will result.
Do not operate with explosive gas mixtures or gases that are
combustible in air. The Hot Cathode sensor has a heated element
and the MicroPirani uses a thin-film Nickel element that is heated to
a constant temperature above ambient. Either of these could ignite
explosive gas mixtures.
Do not substitute parts or modify instrument. Do not install
substitute parts or perform any unauthorized modification to the
instrument. Return the instrument to an Kurt J. Lesker Calibration and
Service Center for service and repair to ensure that all of the safety
features are maintained.

12 Series 979 ATV Transducer
Allow only qualified technicians to service the transducer. Users
should not remove covers, casing, or plug-in components. Injury may
result. A qualified technician must perform any part replacement or
internal adjustments.
Keep the unit free of contaminants. Do not allow contamination of
any kind to enter the unit before or during use. Contaminants such
as dust, dirt, lint, glass chips, and metal chips may permanently
damage the unit.

Series 979 ATV Transducer 13
General Specifications
5x10-10 to atmosphere
5x10-10 to 100 Torr
1 to 9 VDC
1000 Torr
1x10-9 to 10-3 Torr +/- 5% of reading
10-3 to 100 Torr +/- 2% of reading
100 to atm +/- 10% of reading
10-9 to 10-3 Torr +/- 20% of reading
10-3 to 100 Torr +/- 5% of reading
100 to atm +/- 25% of reading
24 VDC
10 Watts
1A @ 30 VAC/VDC resistive load
304 stainless steel, Silicon, SiO2, SiN4,
gold, Ultem®1000, Viton®, glass,
tungsten, platinum clad molybdenum,
yttria coated iridium
304 stainless steel
0.6 cm3
0 to 40oC
100oC
Any
EN-61326-1, EN-61010-1
1” OD tube, mini CF, 2.75” CF, NW16 KF,
NW25 KF, NW40 KF
2.9” x 3.1” x 4.4” (74 x 79.6 x 112 mm)
0.92 lbs. (0.42 Kg)
Measuring range
Set point range
Analog out
Maximum pressure
Repeatability (Typical)
Accuracy (Typical)
Supply voltage
Power consumption
Relay contact rating
Materials exposed to
vacuum
Housing material
Internal volume
Operating temperature
Bakeout temperature (off,
with Hot Cathode electronics
removed)
Installation orientation
CE certification
Vacuum connections
Dimensions (with 1” OD
tube)
Weight (with KF 25)

14 Series 979 ATV Transducer
All user access is through the 15-pin D-sub connector. See the RS-485
Command Set section for more information.
The POWER LED indicates when power is applied to the 979 ATV Transducer.
The FILAMENT ON LED indicates when power is applied to the transducer
filament. The FILAMENT ON light can also be used in conjunction with the
Test RS485 – TST command (described in the RS485 Command Set
section) to visually identify which sensor is set to a particular address. This is
useful when several transducers are connected to the same system.
The figure below shows the front view of the 979 ATV Transducer.
Feature and Control Locations
).$)#!4%36!00,)%$
).$)#!4%3&),!-%.4)3/.

!4642!.$35#%2

Series 979 ATV Transducer 15
The 979 ATV Transducer is designed to measure vacuum chamber pressures
as part of a user’s designed system processes. It combines a Hot Cathode
sensor to measure pressures from 5x10-10 to 3x10-3 Torr and a MicroPirani
sensor to measure pressures from 1x10-3 to atmosphere. Once integrated into
the vacuum system, the 979 ATV Transducer’s functions are computer-
controlled, requiring little manual intervention by the user.This enables the
system to monitor pressure as a procedure invisible to the user, and when the
desired pressure
is reached, trigger
the next event in
the system
process.
This manual
describes the
installation and
configuration
tasks necessary
to set up the 979
ATV Transducer.
After the device is
set up, a software
engineer at the
user’s installation
would use the
communications
protocol described
in this manual to
create a software
program (in, for
example, Visual
Basic, C, or C++)
that will
automatically
control 979
operation.
For additional information on how the 979 ATV Transducer works, see the
appendix How the 979 ATVTransducer Works.
About the 979 ATV Transducer

16 Series 979 ATV Transducer
Typical Applications for the 979
ATVTransducer
♦Measure high vacuum pressure.
♦Control system pressure using digital communications or analog output
as input to an automatic pressure controller.
♦Measure foreline and roughing pressures generated by mechanical
vacuum pumps.
♦Control valves and pumps to automate pump-down using relay set points.
♦Sense abnormal pressure and take appropriate security measures using
relay set points.
♦Start or stop system processes with relay set points.
♦Measure pressures of backfilling gases.

Series 979 ATV Transducer 17
ATV Transducer Installation
Location
Locate the 979 ATV Transducer where it can measure chamber pressure.
Install the device away from pumps and gas sources so it will give the most
representative pressure values. If the Hot Cathode sensor is going to be
baked out, the four screws on the panel closest to the flange will need to be
removed (see the Bakeout section for details). Locate the sensor to ensure
easy access to those four screws.
ENSURE EASY ACCESS TO
REMOVE FOR BAKEOUT
Orientation
The 979 ATV Transducer can be installed and operated in any position without
compromising accuracy.
Installing the 979 ATV Transducer

18 Series 979 ATV Transducer
#&

#& +&
+&
+&












Contamination
Locate and orient the 979 ATV Transducer where contamination is least likely.
For example, if the 979 ATV Transducer is mounted directly above a source of
evaporation, the vapor could contaminate the sensor elements and cause the
calibration to shift. Whenever possible, install the 979 ATV Transducer with
the vacuum port facing down to keep particulates or liquids from entering the
device.To prevent inaccurate pressure measurements, shield an 979 located
near an electron or ion source (e.g., near an electron beam source or in a
sputtering system) and mount it away from strong magnetic fields.
Vacuum Connection
The 979 ATV Transducer is available with the following flanges:
♦2.75” CF (rotatable)
♦1.33” CF (rotatable)
♦KF 16
♦KF 25
♦KF 40
The figure below shows the dimensions for each flange type.The top
dimensions, also shown below, are valid for any flange configuration.

Series 979 ATV Transducer 19
Electrical Connection
Use a cable with a female, 15-pin, high-density D-sub connector with strain
reliefs to ensure proper electrical connection and to reduce stress on the
connectors.
Ensure a low impedance electrical connection between the 979
sensor body and the grounded vacuum system to shield the
sensor from external electromagnetic sources.
Input/Output Wiring
The figure and the 979 ATV Transducer Electrical Connections Table on the
following page identify the pins of the 979 connector and their functions; make
a cable using this information. To comply with EN61326-1 immunity
requirements, use a braided, shielded cable. Connect the braid to the metal
hoods at both ends of the cable with the end for power supply connected to
earth ground.
The power supply input is 24 VDC.The positive side of the power supply is
connected to pin 3 and the negative side to pin 4 of the D-sub connector.
Damage may occur to the circuitry if excessive voltage is applied,
polarity reversed, or if a wrong connection is made.
If using analog output (described in the Analog Output section), the analog
output voltages are pins 5 (+) and 6 (-). Connect them to a differential input
voltmeter or an analog-to-digital (A/D) converter with a differential input in a
system controller.
Do not connect the negative side of the analog output (pin 6) to
the negative side of the power supply input (pin 4) or to any
other ground. Doing so will cause half of the power current to
flow through this wire. Measurement errors in the output
voltage may be seen due to the voltage drop from this current.
The longer the cable, the worse the error will be.

20 Series 979 ATV Transducer
979 ATVTransducer Electrical ConnectionsTable
The digital communications connections are pins 1 and 2. RS-485 uses pin 1
for RS485(-) and pin 2 for RS485(+).
Relay Inductive Loads and Arc Suppression
If using the set point relay to switch inductive loads (e.g., solenoids, relays,
transformers, etc.), the arcing of the relay contacts might interfere with 979
operation and reduce relay contact life. Therefore, an arc suppression
network, shown schematically below, is recommended.
The values of the capacitance C and the resistance R can be calculated by
the following equations:
C = I2/(1 x 107)
R = E/ Ia
where:
C is in farads
R is in ohms
I is DC or Acpeak load current in amperes
E is DC or Acpeak source voltage in volts
a = 1 + (50/ E)
Note that Rmin = 0.5 Ωand Cmin = 1.0 x 10-9 F
RELAY 2 N.O.
RELAY 1 N.C.
POWER +(24V)
POWER -
ANALOG OUT +
RELAY 1 N.O.
RS485 +
ANALOG OUT -
RS485 -
RELAY 1 COMMON
RELAY 3 N.C.
RELAY 2 N.C.
RELAY 3 N.O.
RELAY 2 COMMON
RELAY 3 COMMON
MALE CONNECTOR
ON 979
PIN 1 PIN 5
PIN 6 PIN 10
PIN 11 PIN 15