PD_Rev2_16E-164A-DC_Voltage_Divider_16_June_15_with_attachment_data_req.doc

16E-164A-DC

16 June15

Revision 2

DIRECTORATE OF METROLOGY

PURCHASE DESCRIPTION

FOR

DC VOLTAGE DIVIDER

1.0 SCOPE : This purchase description identifies performance requirements for a DC Voltage Divider, hereafter referred to as the VD. This VD shall be multi-ratio with a minimum capability of Direct Voltage ratios of 1:1, 10:1, 100:1 and 1000:1. The VD shall be of sufficient quality and uncertainty, as described below, that it may be used as a stand-alone reference standard VD and transfer standard VD for a multitude of U.S. Air Force calibration procedures. It is an objective of the Air Force to acquire a VD that does not require a standardization/verification/calibration before each use, whether it is mechanical adjustment or other means. Thereby, a VD of sufficient quality and stability is required, such that an interval much longer than before use may be established.

2.0 COMPONENT : Listed in this purchase description are the Air Force minimum functional requirements which are to be satisfied.

3.0 COMPATIBILITY : This VD shall be compatible with all requirements currently being satisfied by a FLUKE 752A Reference Divider. Thereby the basis of the requirements for this description reflects that of a traditional VD design of series resistances with taps along the series to achieve the required ratios. This purchase description describes additional/enhanced requirements and features beyond those of the existing 752A Reference Divider, which shall be met.

4.0 SALIENT CHARACTERISTICS :

4.1 ELECTRICAL SPECIFICATIONS : The following characteristics represent the maximum allowed VD relative measurement uncertainty. Unless specifically stated otherwise in this purchase description, the following specifications apply when ambient room temperature is within 22.8 oC +/-3.3 oC, are characterized by a 95% Confidence Level, and after a 4-hour VD warm-up period. Where any specification is a combination of sub-specifications, the methodology for combination shall be provided. Additionally, the values, calculation(s) and calculated value(s) shall be provided for all combined specifications.

4.2 RATIO RANGES: A minimum of 1:1, 10:1, 100:1 and 1000:1 shall be provided.

4.3 RATIO UNCERTAINTY: Shall not be worse than the following:

* The contractor shall provide a warranted specification per 4.1 for this value.

4.4 MAXIMUM INPUT VOLTAGE : When applied across the divider Input terminations, the maximum operating voltage shall not be less than 1100VDC. Additionally, all VD terminations shall be protected from irreparable damage due to overvoltage application.

4.5 MEASUREMENT CONFIGURATIONS: This VD shall have capability to be configured to allow relative and direct-ratio measurements of signals input to the front panel terminations for each voltage configuration shown in Diagram 1.0 as a minimum. Additionally, the VD shall be configurable for forward and reverse polarity measurements in same.

10V 0.01V

10V 0.1V

1V

100V

1000V

Diagram 1.0 Configuration(s) Diagram

4.6 POWER COEFFICIENT EFFECTS : Shall be specified for each Ratio and provided by the contractor and shall be included in the Ratio Uncertainty (4.3).

4.7 INPUT/OUTPUT RESITANCE: All Input/Output Resistance specifications shall be determined, specified, warranted and provided by the contractor. The values utilized shall be chosen such that measurement failures, additional errors and other anomalies will not be introduced into measurements requiring use of the VD such as, but not limited to, DC Volts calibration of 5700A, 5720A, 5520A Calibrators, 3485A and 8508A Multifunction Meters and the voltage output shall be comparable/measureable to/with the Air Force Josephson Junction Voltage Standard (JJVS). Issues such as, but not limited to, voltage compliance, current compliance, loading effects and offset current can create measurement problems when Input/Output Resistance is not properly selected. They shall be further selected such that the requirements of this description shall be met and the VD shall not fail to meet Air Force application requirements.

4.7.1 1:1 DIVIDER: In theory, in the 1:1 configuration/mode, the VD Input is connected directly to the VD Output terminations. Thereby, the resistance divider network would not come into play. However, where other technique(s) are provided Input/Output resistance shall be specified and provided by the contractor in the form ohms ±%.

4.7.2 10:1 DIVIDER: Input/Output resistance shall be specified and provided by the contractor in the form ohms ±%.

4.7.3 100:1 DIVIDER: Input/Output resistance shall be specified and provided by the contractor in the form ohms ±%.

4.7.4 1000:1 DIVIDER: Input/Output resistance shall be specified and provided by the contractor in the form ohms ±%.

4.7.5 DRIVEN GUARD: Resistance shall be specified and provided by the contractor in the form ohms ±%.

4.8. ALTITUDE EFFECTS : Shall be specified and provided by the contractor and shall be included in the Ratio Uncertainty (4.3).

5.0 FUNCTIONAL REQUIREMENTS:

5.1 DIMENSIONS: No larger than 7.5 inches (19.1 cm) height, 24 inches (60.96 cm) depth, and capable of fitting into a standard 19 inch (48.2 cm) rack width.

5.2 WEIGHT: 30 lbs.(13.6 kg) maximum.

5.3 ENVIRONMENTAL:

5.3.1 Operating Temperature Range: The unit shall perform to full specifications at 22.8 oC +/-3.3 oC.

5.3.2 Operating Humidity Range: The unit shall perform to full specifications from 20 to 50 % RH.

5.3.3 Storage Temperature: Damage shall not occur to the unit if stored within the following temperature range: -20 oC to +70 oC.

5.3.4 Storage Humidity: Damage shall not occur to the unit if stored within the following humidity range: 15 to 80% RH.

5.4 User Interface: Operations shall be performed using front panel manual controls.

5.5 REMOTE Interface/Programming: (where the VD design provided includes this feature) This item shall be programmable and/ or controlled via an IEEE 488 or IP interface connection by an external controller.

5.5.1 If automated control is possible then either/or

5.5.1.1 Manufacturer software running on Microsoft Windows 7 as a non-elevated user shall be provided.

5.5.1.2 The contractor shall provide full command set and operating control codes to operate with the following:

Operating System: Microsoft Windows 7 non- elevated user Communications Interface: GPIB IEEE-488 or IP Interface

ASCII command strings

It shall adhere to Standard Commands for Programmable Instruments (SCPI) and IEEE 488.2.

6.0 MECHANICAL and Physical Requirements: The instrument of this purchase description shall perform to the following requirements:

6.1 Design and Construction : The equipment will 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 will 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, etc. shall have proper clearance and adjustments. They shall so work together that the equipment will 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 material and parts of this equipment shall be capable of withstanding environmental testing requirements of this specification as specified in paragraph 5.

6.2 Selected Components: Matched and selected components shall be kept to an absolute minimum. Use of specially built non-standard components other than switches and similar individual assemblies shall be avoided whenever possible.

6.3 Metals: Metals shall be of corrosion resistant type or suitably treated to resist corrosion due to atmosphere conditions likely to be met in storage, services or transportation. Dissimilar metals in intimate contact should be kept to a minimum.

6.4 Circuit Boards: Frequent shipping will require that all circuit boards be sufficiently secured by their connectors and be held in place by securing screws or other such hold-down devices.

6.5 Terminations: All terminations shall be insulated binding post, 5-way type, that as a minimum will accept banana plugs, spade lugs and wire, all with equivalent, or better, properties to that of low thermal tellurium copper. The following minimum set(s) of terminations shall be provided and located on the front panel.

6.5.1: Divider Input (HI/LO)

6.5.2: Divider Output(s) (HI/LO), and shall be further configured to allow for direct measurement of all the ratio divided outputs.

6.5.3: Guard

6.5.4: Ground

6.5.5: Reference Standard Input (HI/LO)

6.5.6: Null Detector: The VD shall be designed for use with Analog and Digital types of Null Detectors such that corrections and/or compensation techniques shall not be required to obtain accurate measurements/results. Common instruments for Null Detection within the Air Force inventory are, but not limited to, 8508As, 3458As, AVM-2000s, AVM-100s, 2182s and 845ABs (obsolete).

6.6 Continuous Operation: After a four-hour warm-up period, the equipment shall meet the specifications of this purchase description and shall not display any intermittent characteristics or overheating for an extended period of not less than 120 hours of continuous operation.

6.7 Commercial Air Transportability: The VD shall be suitable for commercial air transport and shall meet all regulations that apply.

6.8 Portability: The accuracies and stability shall not be altered from normal handling and transportation of the VD.

6.9 ANCILLARY/ACCESSORIES: Any and all ancillary equipment/items and accessories (not otherwise specified) needed to perform as described shall be provided by the contractor. This would include, but not limited to, special tools, cables, fixtures, programs and standards.

6.10 CALIBRATION TEST DATA: This VD shall be delivered with the following minimum calibration test data and/or verification test data included for each test point. Each of these data items shall be labeled with the appropriate unit of measure. Where First Production units are required, this data is required to be collected each business day for a period of not less than 90 calendar days and provided with each First Production Unit. Production Units thereafter shall have a minimum of one calibration test data set provided per Production Unit.

6.10.1 Parameter: DC Volts, Ratio (Input/Output).

6.10.2 Applied Value: Value applied by the calibration source to the VD.

6.10.3 Expanded Uncertainty: Uncertainty of Applied Value (6.11.2) at-time-of-calibration and represented by a coverage factor of K=2. This data may be labeled as parts-per-million (ppm) or as µUnit/Unit (i.e. µV/V) and shall be consistent throughout all parameters and test points.

6.10.4 VD Result: Value indicated by the VD as the result of the Applied Value (6.11.2) by the calibration source to the VD. The result should further include the Total Uncertainty (K=2) of the result. Where additional sources of uncertainty exist in the total result beyond that of the Reference Standard and the VD specification, these shall be identified, described, documented and provided by the contractor. The method of mathematical inclusion for uncertainties shall be provided.

6.10.5 VD Specification: The plus and minus value which is the allowable deviation of the VD Result (6.11.4) from the Applied Value (6.11.2), otherwise referred to as PASS/FAIL limits. This data shall be further defined as the better/lesser value of the Purchase Description Specification and the Commercially Published Specification (at 95% confidence), where differences appear.

6.10.6 Data Format: This data shall be provided in a format indicated by the following sample table, or in a format otherwise agreeable to AFMETCAL/WMNEE. All data shall be provided to a resolution adequate to determine the requirements of this purchase description can be verified.

Sample Format Only

0.01

0.1

6.11 Power Supply: (where the VD design provided includes this feature)

6.11.1 Voltage: 120Vrms/240Vrms +/-10%

6.11.2 Frequency: 45Hz to 66Hz

6.11.3 Power Consumption: shall not be greater than 85VA.

6.11.4 Power Cord: 39 inches minimum length.

7.0 Special Hardware/ Software/Licenses Requirements: Any special equipment, fixtures, tools, standards, etc., required to establish Air Force self-sufficiency for calibration and not common to a secondary calibration laboratory shall be supplied with the VD. Any unique accessories including software required for calibration of this item shall be furnished by the manufacturer. Units that fail calibration and are recommended to be aligned or adjusted, either manually or using an automated alignment/adjustment software, the special hardware, manual instructions, software, software instructions and software licenses (where required by the manufacturer, and shall be valid for the life of the instrument) needed to perform the alignment/adjustment process shall be included with the VD. A list of peripheral support TMDE equipment required to accomplish the calibration/alignment/adjustments of the unit shall be provided with the VD. The support TMDE for the VD shall consist of equipment that is currently available in the market place. The VD shall not require support equipment that has been obsoleted and no longer supportable by the manufacturer and/or is not otherwise obtainable/supportable by the Air Force.

8.0 WORKMANSHIP: The workmanship shall be first class, of neat general appearance and shall comply with standard commercial practices. The standards of workmanship shall be such that the VD shall comply with the requirements of this description. All components, subassemblies and final assembly shall comply with the examination and evaluation in Section 10.0.

9.0 SAFETY: Equipment shall be designed such that it will not be of any hazard to itself or to any person operating it using reasonable precautionary procedures.

10.0 QUALITY ASSURANCE: This item shall be inspected and evaluated at destination, as specified elsewhere in this contract. This item will be evaluated with test equipment with parameters equal to or better than those required to assure specified performance requirements are met. Test equipment used is traceable to a National Metrology Institute or other AFMETCAL approved equivalent laboratory when/where required. Evaluations will be performed to assure the item meets the requirements of this purchase description. Such evaluation at destination does not relieve the contractor of performing all inspections and quality checks at the point of fabrication, as specified elsewhere in this contract, or as necessary, to ensure performance, as specified herein. In addition to all elements of this purchase description, all commercially available components provided with this item and the item itself shall, as a minimum, satisfy all commercially published performance specifications (and must be provided by the contractor). Evaluations will also be performed to assure the item meets the requirements of the commercially published performance specifications.

11.0 LICENSING: Where licensing issues apply to any part of the VD, such licensing and associated documents shall be obtained and provided by the contractor. Licenses shall not contravene federal law, federal procurement regulations, or the requirements of this acquisition.

12.0 FIRMWARE: Where firmware technology is employed, when a firmware upgrade is anticipated by the manufacturer during the life of this contract, the contractor shall contact AFMETCAL for concurrence. If AFMETCAL concurs with the proposed upgrade all previous units shall be updated to this upgrade. All firmware or software provided under this contract shall be at the same version, revision and revision date at the completion of the contract.

13.0 INTERCHANGEABILITY: The first system shall be the same as the last system in terms of firmware, software, functionality, and configuration control. All replaceable assemblies, subassemblies, components, and parts of a designated model provided under a single contractor or ordered from any one manufacturer shall be fully interchangeable without interference or degradation of performance.

14.0 Model and Serial Number Identification (IUID):

This item shall be clearly labeled with a model, serial number, and manufacturer’s name. Unique item identification labeling shall follow the Item Identification and Valuation clause as stated in the contract.

1 Attachment:

Data Requirements

Attachment to

Purchase Description 16E-164A-DC

DC Voltage Divider

DATA REQUIREMENTS

MANUALS: A set of operational and maintenance manuals shall be provided. As a minimum, the manuals shall include an explanation of features, performance specifications, operational instructions, theory of operation, calibration procedures, and an illustrated parts breakdown. Wherever possible, use of pictures, diagrams, schematics and mathematical formulas shall be included such that any text material may be better understood. Specifically, the calibration procedure shall include a list of required calibration equipment, by part number, connection diagrams and step-by-step instructions to follow for completing this task. In addition, a system- level manual explaining the system operation and software shall also be provided. Manuals shall be on CD/DVD-ROM in Indexed Portable Document Format (iPDF). A validation and verification of the manuals will be required. The manual shall be in accordance with the Air Force Technical Manual Contract Requirements (TMCR) TM86-01P and Contract Data Requirements List (DD Form 1423).

CALIBRATION CERTIFICATE: A calibration certificate, traceable to the National Institute of Standards and Technology (NIST) or other national metrology institutes (NMIs) shall be provided with each instrument. This calibration certificate must comply with Data Item Description (DID) DI-QCIC-80798B and the Contract Data Requirements List (DD Form 1423).

ACCEPTANCE TEST PLAN: The acceptance test plan shall be delivered to and approved by the government prior to delivery of the evaluation unit. The acceptance test plan shall detail the criteria, performance objectives, and description of tests to be performed. The plan shall be prepared in accordance with Data Item Description DI-QCIC-80553A and Contract Data Requirements List (DD Form 1423).

Null Detector

1:1

UUT

VD

IN OUT

1000:1

Reference Standard

IN OUT

100:1

IN OUT

10:1

IN OUT

OUT IN

10:1

100V

OUT IN

100:1

1000V