Operating Instructions Pirani Vacuum Gauges & Dual Set Point Controllers 0.01 to 100 mTorr (10-5 to 0.1 Torr) 1 to 2000 mTorr .01 to 20 Torr .01 to 100 x 10-3 mbar .001 to 2.000 mbar .01 to 20.00 mbar .001 to 13.333 Pascals 0.1 to 200.
Contents INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Instruments Covered By This Manual . . . . . . . . . . . . . . . . . . . . . . . 2 Vacuum Gauge Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Portable Vacuum Gauge Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Dual Set Point Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . .
1. INTRODUCTION The Vacuum Gauge Indicator and Dual Set-point Controller are compact vacuum measurement and control instruments that offer the precision and high resolution of digital electronics at the same price as analog controls. These instruments introduce a newly developed sensor which incorporates an up-scale trim to improve tracking ability. The extremely rugged sensor is constructed with a solid, inert, noble metal that maintains its characteristics over long periods.
1.1. Instruments Covered By This Manual This manual covers the following instruments: • 0.01 to 20 Torr indicator • 0.01 to 20 Torr indicator and controller • 1 to 2000 mT indicator • 1 to 2000 mT indicator and controller • 1 to 2000 mT portable, battery powered indicator • 0.01 to 100 mT indicator • 0.01 to 100 mT indicator and controller Each of the instruments is designed for a specific pressure range.
1.2. Vacuum Gauge Indicator The indicator instruments are rugged, digital vacuum gauges. They are small, compact instruments that power a Pirani-type gauge tube which senses changes in pressure by measuring the thermal conductivity of the residual gases in the vacuum system. The sensors are made of an inert, noble metal that does not oxidize or corrode. The long-term life expectancy for the gauge tube is excellent if kept clean and free of oil or other evaporated contaminates from the vacuum system.
1.4. Dual Set Point Controller The Dual Set Point Controller instruments are combination controller and indicator digital vacuum gauges. The controllers power a Pirani-type gauge tube which senses changes in pressure by measuring the thermal conductivity of the residual gases in the vacuum system. The sensors are made of an inert, noble metal that does not oxidize or corrode.
2. SPECIFICATIONS • Pressure Range: 0.01 to 100.00 mTorr, 1 to 2000 mTorr, 0.01 to 20.00 Torr, depending on designed range of instrument. • Calibration: Air or Nitrogen. • Accuracy: Better than 5% of value or: (for 100 mTorr gauges) ±0.03 mTorr, (for 2000 mTorr gauges) ±3 mTorr, (for 20 Torr gauges) ±0.03 Torr, whichever is larger. • Set Point Range: Full scale, equal to full scale range of instrument. • Set Point Repeatability: 2 digits. • Analog Output: 0 to 2.
• Line Regulation: ±20% produces less than 1% change in reading. • Dimensions: See drawing at back. • Mounting: Panel mounting hardware is included with each gauge and controller. • Gauge Tube Cables: 10 foot (305 cm) attached; 4 wire for 2000 mT and 100 mT, 6 wire for 20 Torr. • Extension Cables: Change gauge tube cable length without recalibration. Extensions to 500 feet (150M) can be provided. • Relay Output: 3 pin screw terminal connectors. • Line Cord: 5 1/2 feet (170 cm) long.
3. INSTALLATION 3.1. Unpacking Instructions The instruments and gauge tubes are carefully packaged to protect them during shipment. Use reasonable care when removing them from the shipping box. Inspect the instruments and gauge tubes carefully when you receive them. Should either the instruments or the gauge tubes show any signs of damage, file a claim with the carrier immediately. Do not destroy the shipping container. It will be required by the carrier as evidence to support claims.
3.2 Panel Mounting 1/4 DIN Enclosure 3.5" (89 mm) 3.78" (96 mm) 4.
Both the digital indicators and dual set-point controllers mount in a single panel cut out. Instruments provided in “standard enclolures” fit the same 2.75" (70 mm) round hole as used by Hastings, Televac, Lesker, Varian and other analog meter instruments. A ‘U’ shaped panel mounting clip is included with the instrument. Instruments provided in 1/4 DIN Enclosures fit a 92 mm x 92 mm cut out. Jack screws are included with 1/4 DIN instruments. 1.
3.3. Gauge Tube Installation 1. Thread the gauge tube into a 1/8 inch NPT female fitting (or other fitting or flange as per your gauge tube), in the vacuum system. The preferred mounting is with the open end pointing down so as to be self draining to any condensation. However, mounting in any position is acceptable. 2. An appropriate thread sealant is required to insure that the threaded connection will not leak.
4. OPERATING INSTRUCTIONS 4.1. Readings On The Display When the power is applied and the gauge tube connection is made, your instrument is in operation. After a short time period for stabilization, the digital display will show a reading of vacuum pressure. At atmospheric pressure, and at pressures above the designed range of the instruments, the display will show a “1” with the other digits blanked out. This indicates saturation.
4.2. Setting the Control Points To set the control points, press in either the Low or High “Push To Display” push-button on the front panel. This will display that set point on the digital meter. Adjust the multi-turn pot that corresponds to that set point until the desired pressure for the control action is read on the meter. The set point adjustment pots are located on the front panel on either side of the LEDs. Release the “Push To Display” push-button and the instrument will again read pressure.
4.4. Analog Output Signal Rear Panel of Digital Instruments Unplug the gray plastic connector from the instrument Center terminal is positive Outer terminal is common Vacuum gauges are shipped with a removable connector for analog output plugged into the rear panel of the instrument. Follow the steps below to wire the connector for output to remote recorders, dataloggers, etc. 1. Unplug the gray connector from the rear panel. 2. Unscrew the gray plastic connector cover. 3.
4.4.1 Optional 4-20 mA and 0-5 or 0-10 VDC Output Gauges provided with an optional output are built in 1/4 DIN size cabinets which mount in 92 mm square panel cut-outs. On the rear panel of the instrument you will find a section identified as “analog output” which includes the zero and span adjustment potentiometers and a male connector for the 4-20 mA, 0-5 or 0-10 VDC outputs. Unplug this connector and unscrew the gray plastic shroud.
4.5.1 Offset & Span Adjustment Using Reference Calibrator Purchase a reference gauge tube calibrator from the manufacturer or your supplier. The calibrator is marked with the three proper settings for adjustment of zero, span, and offset. A simple toggle switch selects the “zero” and “span” and “offset” circuits so that you can make the proper adjustments using the associated zero, span and offset pot. All three adjustment pots are located on the rear of both the indicator and controller instruments.
4.5.2. Setting Zero And Span Using Manometer This method requires a high vacuum system and a precision calibration “standard” such as a capacitance manometer. If these are not available, use the reference tube technique described previously. The procedure below lists ranges and settings for a 2000 mTorr instrument as an example.
4.6. Cable Extensions The indicator and controller models are unique in their ability to change cable lengths without requiring recalibration. Typically, for a 2000 mTorr instrument, a 500 foot cable of #18 wire may be added with less than 1 mTorr error. If factory cables are purchased with the instrument, it will be calibrated with that cable. Customers making their own cables may do so to any length, provided the wire resistance is kept at 3.2 ohms or less per lead, e.g. 500 feet of #18 wire is 3.19 ohms.
4.7. Three & 5 Position Gauge Tube Selector Switch Operation Use the 3 or 5 Position Gauge Tube Selector Switch as an accessory with the indicator instruments. Plug the male connector of the 3 or 5 Position Selector Switch into the gauge tube cable of the indicator. Then connect one, two, three, four, or five (depending on model) separate gauge tubes to the gauge tube cables of the switch.
5. TECHNICAL DATA 5.1. Troubleshooting It is strongly recommended that every customer keep a small stock of spare gauge tubes on hand along with a Reference Gauge Tube Calibrator. Always try a new tube before considering circuit failures. The Reference Gauge Tube Calibrator may be connected to the circuit to prove whether the problem is a gauge tube or circuit failure. If the instrument works properly with the Reference Gauge Tube Calibrator circuit, then gauge tube failure is a certainty. 5.2.
5.3. Changing Operating Line Voltage The operating voltage for instruments can be changed in the field by changing the connection across four pads on one of the circuit boards. For access to these pads, remove 2 screws in rear of the cylindrical outer cover. Slide the cover back, completely away from the circuit boards. Locate the four pads on the edge of the circuit board where the power cord comes to the circuit board.
Our standard gauges are shipped without a resistor in the R-5 position in the high relay circuit and without a resistor in the R-13 position in the low relay circuit. This produces about ± 1 digit hysteresis. Installing resistor values as shown in the table will increase the hysteresis. Keep in mind that these are digits, not mTorr, Torr, or any other pressure unit. ±10 digits is ±10 mTorr on a 2000 mTorr full scale instrument. On an instrument with full scale of 20.00 Torr ± 10 digits is +/-.10 Torr.
6. WARRANTY AND RETURN PROCEDURE 6.1. Warrany Statement The manufacturer warrants all instruments for a period of two years against defects of material and workmanship subject to the terms and conditions set forth below: 1. The warranty is in effect at date of shipment from the manutacturer to the original purchaser. 2. Expendables such as gauge tubes, etc. are not covered by this warranty. 3.
7. PARTS AND ACCESSORIES Gauges and Controllers 0.01 - 100 mTorr Dual Set Point Controller......................................902005 0.01 - 100 mTorr Indicator................................................................902006 1 - 2000 mTorr Dual Set Point Controller.........................................902001 1 - 2000 mTorr Indicator...................................................................902002 1 - 2000 mTorr Portable, Battery Powered Indicator........................902017 0.
8. DIMENSION DRAWINGS Indicators and Controllers Are Available In 2 Enclosure Styles 0.50" (13 mm) Max. Panel Thickness 3.5" (89 mm) Ø2.75" (70 mm) 4.84" (123 mm) Standard Enclosure The standard enclosure has a cylindrical body that fits the same 2.8 inch diameter panel cutout as Hastings, Televac, and other gauges. Panel mounting hardware is included with standard enclosure. 3.78" (96 mm) 3.5" (89 mm) PANEL MOUNT JACK SCREW 4.
1 To 2000 mTorr Portable Battery Gauge To adjust Zero, Span and Offset use 2000 mT calibrator P/N # 912008 To adjust THR use 1000 mT calibrator P/N 902114 0.01 to 20.
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