Watt Meter  Model 2330
POWER AND ENERGY
HIGHLY ACCURATE
EXTREMELY
BROADBAND
NIST
TRACEABLE 

TRUE RMS/REALLY BROADBAND
The Model 2330 Sampling Watt Meter is a precision, high accuracy,
autoranging watt meter which simultaneously measures and displays true rms Voltage,
true rms Current and true mean Power over a frequency range from dc to more than 600kHz.
Full scale Current and Voltage inputs are typically measured within ±0.1%
of the reading in amplitude to at least 400kHz. The corresponding Power is typically
measured to within ±0.1% of the input VoltAmperes to 200kHz
and to within ±0.2% of the input VoltAmperes to 400kHz for
loads of any Power Factor.
MULTIFUNCTION (ENERGY)
In addition to the rms Voltage, rms Current, and mean square Power the Model 2330 watt
meter also measures simultaneously the peak Voltage, the peak Current and the
Frequency and calculates the VoltAmpere product, the Power Factor and the Energy
accumulated over a period of time from 199 hours. These functions may be displayed or may
be read over the IEEE488.2 interface. The Energy function makes compliance
with the Federal Guidelines for Standby Power Use quite straight forward.
(Executive Order 13221)
UNPARALLELED HIGH FREQUENCY ACCURACY
The Model 2330 watt meter allows broadband and high accuracy measurements of both
sinusoidal and highly distorted wave shapes. The Current, Voltage, Power, and Power Factor
accuracies to 400kHz of the Model 2330 far exceed any other sampling VoltAmpereWatt
Meter, or for that matter, with respect to Current or Voltage, almost all conventional
multimeters. Although reduced by a factor of two, excellent accuracy is maintained to
600kHz.
Full scale Power ranges exist for loads with impedances from (0.6V/1.5A) = 0.4W to (600V/1.5mA) = 400kW.
WIDE MEASUREMENT RANGE
The Model 2330 watt meter has full scale Power ranges from 1.0000mW to 10000W. With
external shunts or current to voltage transducers the upper range may be extended by a
factor of ten or one hundred. Full scale Voltage from 2.000V to 2000V (usable to 600V) and
full scale Current ranges from 5.000mA to 5.000A (all rms values) cover a wide range of
load impedances. Full scale Current and Voltage inputs may have crest factors up to three
while smaller inputs may have even higher crest factors. Sinusoidal inputs with rms values
of twice the nominal Full Scale value may be measured with no loss in accuracy.
POSSIBLE MEASUREMENT USES
Measurement of Ultrasonic Equipment of all types and power levels, Finished Transformers,
Transformer Core Material, Switching Power Supplies, Fluorescent Lamp Ballasts of all
types, Mercury Arc Lamp Circuits, Sodium Lamp Ballasts, Speed Controlled Motors of all
types, Efficiency of any device with an electrical input and an electrical output, SCR
Controlled Devices of all types, High Frequency and/or Distorted Currents from any source,
Voltage Response of any device from DC to 600kHz, and the Characteristics of Electric
Automobile Drives.
EASY TO CALIBRATE AND MAINTAIN
The Model 2330 watt meter is an all solid state instrument with optically isolated input
channels. All integrated circuits are in sockets. DC coupling in both channels allows
calibration and/or verification with high accuracy dc sources. Internal software
calibration routines allow most recalibrations to be accomplished without
screwdriver adjustments.
UNIQUE SAMPLING APPROACH / ISOLATED INPUTS
The Voltage and Current inputs of the Model 2330 watt meter are simultaneously sampled
(with 16 bit resolution), converted to digital form, and transmitted via optical links to
the main chassis. This allows both the Current and Voltage inputs to be completely
isolated from each other and from the main chassis. The asynchronous sampling frequency is
controlled by the system microprocessor in such a fashion that neither it nor any of its
harmonics can come close to the measured input frequency or any of its harmonics. This
precaution prevents "beats" with their accompanying jitter in the displayed
values.
IEEE488.2 BUS CONTROL
The Model 2330 watt meter is equipped with an IEEE488.2 interface which incorporates all
of the Common Commands and Queries. Any function that can be entered via the front panel
can be controlled via the IEEE bus. In addition, any or all of the functions which can be
displayed, can be queried and sent simultaneously to the Controller over the bus. The
status (e.g. Current range, Voltage range, etc) of the instrument may also be queried and
sent over the bus. The bus address is set from the front panel and is displayed both at
turnon and when the Local key is depressed. A Remote lamp indicates that the watt meter
has been placed in its Remote state by the Controller.
SPECIFICATIONS
VOLTAGE
Range, Resolution and Input Impedance:
Full Scale
RMS Voltage 
Calibrated
Peak Range 
Resolution 
Input
Impedance 
2.000V 
0  6V 
1mV 
1.05MW/15pF 
20.00V 
0  60V 
10mV 
1.01MW/15pF 
200.0V 
0  600V 
100mV 
1.00MW/15pF 
2000 V* 
0  850V 
1 V 
1.00MW/15pF 
*The 2000V range is useable to 600V rms 
Uncertainty:
(rms) 

±0.10% of reading ±2 digits from 5Hz to 200kHz and dc
±0.20% of reading ±4 digits from 200kHz to 400kHz
±0.40% of reading ±8 digits from 400kHz to 600kHz 
Uncertainty:
(peak) 

±0.10% of reading ±4 digits from 5Hz to 200kHz and dc
±0.20% of reading ±8 digits from 200kHz to 400kHz
±0.40% of reading ±16 digits from 400kHz to 600kHz 
Isolation: 

1000V may be placed between LO Voltage Terminal and Chassis 
CURRENT
Range, Resolution and Input Impedance:
Full Scale
RMS Current 
Calibrated
Peak Range 
Resolution 
Input
Impedance 
5.000mA 
0  15mA 
1mA 
20 W 
50.00mA 
0  150mA 
10mA 
2 W 
500.0mA 
0  1500mA 
100uA 
0.33 W 
5000 mA 
0  15A 
1mA 
0.04 W 
EXTernal*
(100mV) 
0  300mV 
 
20 W 
*The Display on the EXT range is factory settable to read
any value up to 5000, with any positioning of the decimal point, for a 100mV input.
The 5000mA range is specified to only 400kHz. 
Uncertainty:
(rms) 

±0.10% of reading ±5 digits from 5Hz to 200kHz and dc
±0.20% of reading ±10 digits from 200kHz to 400kHz
±0.40% of reading ±20 digits from 400kHz to 600kHz 
Uncertainty:
(peak) 

±0.10% of reading±10 digits from 5Hz to 200kHz and dc
±0.20% of reading ±20 digits from 200kHz to 400kHz
±0.40% of reading ±40 digits from 400kHz to 600kHz
The 5000mA range is specified to only 400kHz. 
Isolation: 

1000V may be placed between LO Voltage Terminal and Chassis 
POWER AND POWER x10
Ranges: 
Eight decade Full Scale ranges from 1.0000mWatt to 10,000Watts. The ranges
are all combinations of a Full Scale Current range multiplied by a Full Scale Voltage
range plus a corresponding set of combinations with ten times the sensitivity which occur
when the Px10 range is activated. The Px10 range may be selected when both the
Peak Current and the Peak Voltage are less than 0.316 of their Calibrated Peak Range
values. 


Resolution: 
1 part in 10000 of the Full Scale range 


Uncertainty:
(for any Power Factor) 
±0.10% of VA ±10 digits from
5Hz to 200kHz and dc
±0.20% of VA ±20 digits from 200kHz to 400kHz
±0.40% of VA ±40 digits from 400kHz to 600kHz
(VA is the VoltAmpere product)
The Power uncertainty is specified to only 400kHz when the 5A Range is
active. 
VOLTAMPERES
Calculated as the product of the rms Current and the rms Voltage. It has the same
Full Scale ranges, resolution and uncertainty as POWER.
POWER FACTOR
Calculated as the ratio of Power to VoltAmperes. It has a range from 0 to ±1.0000
and a resolution of .0001 for VoltAmpere products greater than 7.5% of Full Scale.
The resolution decreases as the VoltAmpere product decreases. The uncertainty is
±0.001 ±10 digits up to 200kHz and ±0.002 ±20 digits from 200kHz to 400kHz .
ENERGY
Calculated as the integral over time of the Power consumed by the Device under test.
Positive Energy has a resolution of 6 digits while negative Energy has a resolution of 5
digits. Energy may be accumulated for up to 99 hours in 1 hour increments (or
arbitrary increments when using the IEEE488 interface).
FREQUENCY
Frequency of Voltage or Current from 5.0000Hz to 640.00kHz with five digits of resolution
and an uncertainty of ±100ppm ±1 digit.
DISPLAYS
Three LED (10.9mm/.43 inch high) Displays. Two four digit displays for Current
and Voltage and a six digit display for Power and the other functions.
IEEE488.2 INTERFACE SUBSETS: SH1, AH1, T6, L4, SR1, RL1,
PP0, DT0, DC1
DISPLAY UPDATE 
10 times a second 


SETTLING TIME 
5 seconds to reach 0.1% of Full Scale 
TEMPERATURE RANGE

Operating 
0°C to 40°C 

Within Specifications 
18°C to 25°C 

Storage 
40°C to
75°C 

Derate specifications by a factor of 2 when
operating outside the 18°C to 25°C temperature bracket. 


RELATIVE HUMIDITY 
Less than 90% 


WARMUP TIME 
Thirty minutes for all specifications 
POWER REQUIREMENTS

100V ±10%, 120V ±10%, 220V ±10%, 240V ±10% (Rear Panel switch
selectable) 50Hz to 400Hz. 1/2A AGC Fuse for 120V operation.
Power Consumption less than 24Watt (60Hz120V). 
PHYSICAL

Rack Mount kit available as an option 

Weight: 
6.85kilograms (15pounds) 

Size: 
43.2cm x 13.3cm x 33.0cm (17" x 5.25" x 13") 
