Contents: Section 1 Overview...2 Section 2 Apparatus...3 Section 3 Safety Note...4 Section 4 Consecutive Testing...5 Section 5 Preparation...6 Section 6 Testing Procedure...7 Section 7 Completing Lighting Assemblies...8 Section 8 Calculations...9 Section 9 Failure of Assemblies...10 Texas Department of Transportation 1 TxDOT 11/2004
Section 1 Overview Section 1 Overview This method describes the apparatus and procedures used to determine electrical characteristics of ballasts designed to operate lighting assemblies. This method replaces Test Method "Tex-877-B, Ballasts of Lighting Assemblies." Texas Department of Transportation 2 TxDOT 11/2004
Section 2 Apparatus Section 2 Apparatus The following apparatus is required: Transformer, variable capable of obtaining voltages from 0 to 560 volts AC Volt-amp-watt (VAW) meter with minimum accuracy of 99.5% for volts and amperes, 98.5% for watts at 100% power factor, and 97.0% for watts at 50% power factor Volt-ohm meter Oscilloscope 2 channel and 50 MHz or better Probe, 1000X attenuator Probe, 10X attenuator Resistor, 2.0 ohm, 25-watt. NOTE: The above units may be connected in a test bench arrangement to facilitate testing large numbers of lighting assemblies. Texas Department of Transportation 3 TxDOT 11/2004
Section 3 Safety Note Section 3 Safety Note Refer to 'Safety Note' in the "Overview" of this manual. Texas Department of Transportation 4 TxDOT 11/2004
Section 4 Consecutive Testing Section 4 Consecutive Testing Testing of ballasts may be conducted consecutively with starting aid performance tests described in Test Method "Tex-1140-T, Electronic Starting Aids of High Pressure Sodium Vapor Lighting Assemblies," or as a separate operation. If conducted consecutively, Test Method "Tex-1130-T, Ballasts of Lighting Assemblies," should be performed first. Texas Department of Transportation 5 TxDOT 11/2004
Section 5 Preparation Section 5 Preparation The following table details the steps for preparing the assembly and apparatus for testing the electrical characteristics of the ballast. Preparing Assembly for Ballast Testing Step Action 1 Remove all power from test bench. 2 Make proper electrical connections to the ballast input, ballast output, and lamp input. 3 Install lamp in remote test box. 4 Select proper center-rated operating voltage for ballast. 5 Following all safety precautions, turn on power to test bench. Turn on test equipment and allow warming up a minimum of 30 minutes, initially. 6 Slowly adjust the transformer voltage to apply center-rated operating voltage to the lighting assembly. 7 Allow lighting assembly to burn-in for a minimum of 30 minutes. Texas Department of Transportation 6 TxDOT 11/2004
Section 6 Testing Procedure Section 6 Testing Procedure The following table details the steps for testing the assembly against specification requirements. Ballast Testing Step Action 1 Repeat steps 2 to 7 for each of the following voltages: Center-rated operating voltage Maximum calculated voltage, and Minimum calculated voltage. NOTE: See pertinent specification. 2 Adjust the ballast input voltage as appropriate. 3 Record the ballast wattage and amperage on the test sheet. 4 Connect VAW meter to the lamp input. 5 Record the lamp wattage and voltage on the test sheet. 6 Connect the VAW meter to the ballast input. 7 Adjust the ballast input voltage to center-rated operating voltage. 8 If Test Method "Tex-1140-T, Electronic Starting Aids of High Pressure Sodium Vapor Lighting Assemblies," is to be performed, proceed to 'Completing Lighting Assemblies.' 9 Turn transformer knob to zero as indicated on the reference dial. 10 Remove power from the test bench. Texas Department of Transportation 7 TxDOT 11/2004
Section 7 Completing Lighting Assemblies Calculate Power Factor for each assembly. Section 7 Completing Lighting Assemblies Calculate Lamp Fluctuation for each assembly. If Test Method "Tex-1140-T, Electronic Starting Aids of High Pressure Sodium Vapor Lighting Assemblies," is to be performed, proceed to Test Method Tex-1140-T. Otherwise: Follow 'Tagging/Labeling, Documenting and Shipping General Requirements' as detailed in the "Overview" of this manual. Texas Department of Transportation 8 TxDOT 11/2004
Section 8 Calculations Section 8 Calculations Use the following to calculate the power factor and lamp fluctuation. Power Factor: PF.. = W/( VxA) Where: P.F. = Power Factor W = Wattage at center-rated voltage C.V. =Center-rated voltage A = Amperes at center-rated voltage. Lamp Fluctuation: (W max. W min.) fluctuation= W nom. Where: W max. = Lamp wattage at maximum voltage W min. = Lamp wattage at minimum voltage W nom. = Lamp wattage at nominal voltage. Texas Department of Transportation 9 TxDOT 11/2004
Section 9 Failure of Assemblies Section 9 Failure of Assemblies Any assembly that fails to meet specification will be rejected and the lot represented by that assembly shall also be rejected. Texas Department of Transportation 10 TxDOT 11/2004