Rotek 800A - Use as a Voltage Source; Use as a Current Source; Model 811 A;811 AE; Energy Instruments with Electrical Pulse Output

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value times the Power Factor setting - if either is used. When this is accomplished the Error display
reads the error in % of setting directly for fractional divider settings and % of output divided by 1/PF
for power factor settings. Note that for Power Factor settings of zero the Deviation function is
disabled; since any error at zero power represents an infinite percentage.
2.4.8 Use as a Voltage Source
The Model 800A may be used to generate accurate AC voltages from 10 to 750 volts for AC
voltmeter calibration. For this purpose place a short between the two current output terminals.
Follow the procedure for entering voltage. Operate may be asserted any time that the entry LED
indicator is in the Key Volt-Amperes field or beyond.
2.4.9 Use as a Current Source
The Model 800A may be used to generate accurate AC currents from 0.011 to 50 amperes
for meter calibration. Follow the procedure for entering voltage and set the voltage to 100 volts.
Follow the procedure for entering Volt-Amperes and set the volt-amperes to the desired current
output times 100. For example, to generate 0.1 amperes set the power to 10 volt-amperes; to
generate 50 amperes set the power to 5000 volt-amperes.
2.4.10 Model 811A/811AE
The Rotek Model 811A may be used to calibrate wattmeters in the same manner as the
Model 800A. All paragraphs of section 2.4.1 apply to the operation of the 811A. In addition, the
Model 811A may be used to calibrate rotating or electronic energy meters.
To accomplish this, the Model 811A has a built-in, crystal controlled, real time clock which
may be applied to generate a precise time interval and thus a precise amount of energy. This internal
clock may also be counted over an externally controlled interval (such as the time between two or
more consecutive pulses from a photoelectric pickup) allowing a precise measure of energy.
How these features are employed depends on the construction of the energy instrument
being inspected. The best means of illustrating the use is through example.
2.4.11 Energy Instruments With Electrical Pulse Output
Instruments such as the Radian Research RM-11, Scientific Columbus SC-10, SC-60, Micro
Joule and the Duncan J-6, among others, produce a pulse train output, the rate of which is
proportional to the applied power. In the case of an SC-10 with a K
h
of 0.6, the total number of
pulses produced is proportional to the applied energy by the relation of 1000 pulses per 0.6 watt-
hours.
A simple test which calibrates the SC-10 checks this conversion constant. A constant power
of 600 watts is applied to the SC-10 and the 811A will be used to determine the amount of energy
required to generate 10000 pulses. Since,
1000 0 6
0 6 3600
2160
pulses watt - hours
watt -seconds
watt -seconds
=
=×
=
.
.