PD_Rev1_26M-218A-VA Cold Cathode Gauge Replacements.docx

26M-218A-VA

December 18, 2025 Rev 1

PURCHASE DESCRIPTION

FOR

Vacuum Gauge Standard

1.0 SCOPE: This purchase description outlines the minimum requirements for a Vacuum Gauge Standard (VGS). The VGS shall consist of a controller, sensor modules, associated sensors (gauge tubes), and necessary communication cables. This procurement aims to replace the existing Televac MM200(W)2-2100-267 vacuum gauge system. The VGS will be calibrated by the Air Force Primary Standard Laboratory (AFPSL) using high-accuracy standards traceable to NIST. The VGS will serve as a base reference standard for calibrations in Air Force Precision Measurement Equipment Laboratories (PMELs), supporting composite repair systems, clean rooms, research and development, space simulation, and aircraft maintenance.

2.0 PERFORMANCE REQUIREMENTS:

2.1 Operations: The VGS shall consist of a basic electronic unit and modular sensor signal processing interface. Users are expected to interact primarily with the system's main display panel during operation.

2.2 Operational Range: The VGS shall be capable of measuring vacuum levels at least within the range of 1 X 10-6 Torr to 1 X 10-3 Torr

2.3 Pressure Uncertainty: The VGS shall have an uncertainty of at most the following for the respective defined ranges:

2.3.1 1E-06 to 1E-05 Torr: ± 3E-06 Torr 1E-05 to 1E-04 Torr: ± 3E-05 Torr 1E-04 to 1E-03 Torr: ± 3E-04 Torr

2.3.2 Uncertainty shall include, but not limited to the combined effects of, hysteresis, repeatability, linearity, temperature compensation, and calibration standard uncertainty (See 2.3.3 for input values).

2.3.3 Calibration standard’s uncertainty input: ± 5% RDG

2.3.4 The VGS shall be capable of maintaining its uncertainty for a minimum of 12 months without the need of alignment.

2.4 Resolution: The VGS shall be able to display a resolution of 4 digits.

2.5 Environmental Requirements: The VGS shall be able to operate or be stored in the following environmental conditions:

2.5.1 Operating Temperature: 65°F to 80°F

2.5.2 Operating Humidity: Maximum relative humidity 80%

2.6 Warm-Up Time: The VGS shall require a warm-up time of not greater than 30 minutes.

3.0 FUNCTIONAL REQUIREMENTS:

3.1 Display: The VGS shall have a digital display capable of displaying its measurements with a resolution equal to or better than the set uncertainty in paragraph 2.4.

3.1.1 Front Panel Controls: All modes and functions of the equipment shall be operable using front display panel controls.

3.1.2 Units: The VGS shall have, at a minimum, the following units of pressure:

3.1.2.1 Torr, Pa, mbar, and at least one user defined unit.

3.1.3 Stability Limit: The VGS shall have a user-adjustable stability limit.

3.1.3.1 Stability Indication: Once the set stability limit has been achieved, a visual indication is given on the VGS.

3.1.4 Medium: The VGS shall operate with dry nitrogen and air.

3.1.5 Operator Calibration: The VGS shall allow for alignment, either through adjustment mechanisms or curve fitting, to meet the accuracy requirements in Para 2 for displayed and transmitted measurements.

3.2 Communication: The computer interface must provide a means for electronic communication with the gauge controller using RS232 to an external controller.

3.3 Overpressure Protection: The VGS shall have a maximum pressure safety feature to protect the system by disabling power to the cold cathode gauge.

4.0 MECHANICAL & PHYSICAL REQUIREMENTS:

4.1 Size and Weight:

4.1.1 The VGS display weight shall not exceed 10 lbs.

4.1.2 The VGS display dimensions (LxWxH) shall not exceed 15”x 10”x 5”.

4.2 Shipping/Carrying Case: Reusable case shall be provided with the VGS for the purpose of shipping the necessary components of the system that require calibration. The case shall be rugged, rigid, waterproof, and capable of withstanding shock and vibration from day-to-day shipping.

4.3 Vacuum Connections: The VGS sensor shall have a 0.75 inch straight pipe port for vacuum connection. Any additional connections, fittings, adapters, or miscellaneous hardware shall be supplied for the system to meet the PD.

4.4 Construction: The VGS shall be designed and constructed of materials that meet the requirements of this specification and in accordance with the best commercial practices for industry approved equipment. It shall be the contractor’s responsibility to assure the government that such design objectives as reliability, accuracy of operation, maintainability and ease of operation have been given due consideration in the manufacture of this equipment. All parts such as shafts, bearings, regulators, switches, controls, connectors, etc., shall have proper clearance and adjustments. They shall work together so that the equipment shall supply the rated requirements without unnecessary strains, vibrations, and overheating. They shall be able to withstand the conditions met in shipping, storage, installation, and services. All materials and parts of this equipment shall be capable of withstanding environmental testing requirements of this specification.

4.5 AC Power Rating: The power required to operate the VGS shall be ~120 VAC at 50/60 Hz single phase.

4.5.1 The VGS shall not use more than one outlet.

4.5.2 Necessary detachable power cords shall be provided.

4.6 Individual Unique Identifier Designation: The VGS shall be clearly labeled with a model number, serial number, and manufacturer’s name. Unique item identification labeling shall follow Item Identification and Valuation requirements as stated in the contract. The VGS shall be clearly labeled with an expiration date of the Warranty Agreement.

4.7 Electrical Protection: If the VGS operates on AC line power, it shall have a fuse or circuit breaker to protect it in the event of excessive current. The AC line power fuses shall be user serviceable without removing any covers /panels or voiding a manufacturer’s service warranty.

5.0 FIRMWARE/SOFTWARE:

5.1 Firmware Identification: Firmware version shall automatically display upon startup. All firmware used in conjunction with instrument shall be identified by Name and Version, which is to be displayed upon startup or located in an “About” menu in the firmware.

5.2 Communication Cables: The VGS shall include a communication cable between the sensor and the controller that has length of four to six feet.

5.3 Firmware Warranty:

5.3.1 The contractor shall warrant that the firmware product meets this purchase description and is free from defects in design and operation and will perform to stated specifications within this purchase description.

5.3.2 The contractor shall (at no additional cost) update or replace the firmware product as necessary to correct any deficiencies identified in the firmware. Replacement firmware shall meet or exceed the requirements in this purchase description. This condition applies to all units purchased under this contract.

5.4 Additional Hardware: Additional hardware required to make this system function as identified by this purchase description shall be provided by the offeror.

6.0 OPERATOR’S MANUAL: A Commercial Off the Shelf (COTS) operator’s manual shall include the following:

6.1 Individual Component Listings: The manual shall list the field replaceable components, which includes OEM manufacturer’s name, and OEM part number. If applicable, include component range and uncertainty.

6.2 Calibration and Alignment Procedures: The manual shall have calibration (verification) and alignment procedures for calibrating and aligning the vacuum sensors.

6.3 Remote Command Listings: The manual shall list the input/output parameters, command strings and other pertinent data required to accomplish remote operation of the VGS.

7.0 Deliverable Component List: A comprehensive list of all components expected with the delivery shall be provided with each shipment. The list at a minimum shall include the P/N, noun, and quantity.

8.0 Environment, Safety, and Operational Health: A combination of the system manual, other documentation, and/or the system itself shall identify potential environment, safety and operational health hazards and how they are mitigated when the design itself cannot mitigate them. This will be accomplished through stating the hazard and accompanying mitigation through the use of safety devices, use of warnings, or use of special operational procedures to counter such hazards.

9.0 WARRANTY & TECHNICAL SUPPORT: A warranty and technical support normally offered by the vendor for this product shall be provided with the unit. The warranty shall last at least one year from delivery.

10.0 TESTING: The VGS will be inspected and accepted at a destination specified elsewhere in this contract. The item will be checked with test equipment and parameters equal to or better than those required assuring specified performance requirements are met. Test equipment has first echelon certification directly traceable to the National Institute of Standards and Technology (NIST) or other AFMETCAL approved sources where required. Test will be performed to assure the VGS meets or exceeds all of the requirements of this purchase description. Such testing does not relieve the contractor of performing all inspections and quality control checks at the point of fabrication as necessary to assure performance as specified

Attachment:

Data Requirements