Two models - 1908 and 1908P
The 1908 multimeter incorporates a USB interface for remote control and readback. The 1908P incorporates USB, RS232, GPIB and LXI compliant LAN interfaces making it suitable for a wider range of system applications. Both models can operate from either AC-line power or internal batteries, but the 1908P requires AC-line power when using the remote interfaces.
Dual display and dual measurement system
The 1908 has both a main display and a secondary display.
- The two displays can be used for a variety of purposes:
- To display a measurement along with the selected range (e.g. 100 Vdc).
- To display a measurement in two different units (e.g. ac volts and dBm).
- To display the result of a calculated function (e.g. value and % deviation).
- To measure and display two parameters of one signal (e.g. ac and dc volts).
- To measure and display two different signals (e.g. ac volts and dc current).
Internal rechargeable batteries for ‘use anywhere’ versatility
Unlike most high performance bench multimeters, the 1908 and 1908P can operate without AC power whenever required. The batteries are charged from the internal power supply and can give more than 35 hours of operation. This enables the meter to be used in locations where no AC line power is available, or moved around multiple room locations without the nuisance of having to find a power socket. When precision measurements are needed, handheld portable multimeters may not be up to the task. The 1908/1908P not only offers fully portable precision, but also built-in data logging for remote locations.
Capabilities in details
Automatic or Manual Ranging
Quick response auto-ranging is provided for all measurement parameters ensuring the best possible resolution at all times. Alternatively manual ranging can be selected. The secondary display can show the range value, giving greater clarity.
Wideband True RMS AC
True RMS ac gives accurate measurements regardless of the waveform shape. The wide bandwidth attenuator provides high accuracy within the audio band and gives extended response to avoid errors when measuring switching waveforms. Measurements are normally ac coupled but, when required, the true RMS value of the ac plus dc components can be shown.
Frequency & Capacitance
High accuracy frequency measurement (better than 0.01%) is available from 10Hz to 120kHz. A reciprocal counting technique is used to give up to 0.01Hz resolution and fast update. Capacitance measurement is also built-in with five ranges up to 120µF.
Temperature Measurement
Linearised measurement is incorporated for PT100 and PT1000 platinum resistance temperature detectors (RTDs). It can use either a 2 wire or 4 wire connection and can be displayed in oC or oF.
Smart functions for added power
Linear scaling with offset
This function enables a reading to be multiplied by a scale factor (A) and for an offset (b) to be added or subtracted. This means, for example, that the electrical output of a transducer can be scaled to give a direct readout of the physical parameter e.g. temperature or weight. It is particularly useful with 4-20mA current loops.
dB measurements
AC voltages can be displayed in dB as well as voltage. Built-in zero reference scaling enables voltages to be displayed in dBm relative to a choice of impedance from 50W up to 8kW. The voltage can be displayed simultaneously in the secondary display.
Limits comparison
This function enables the reading to be tested against high and low limits set by the user. The display then shows HI, LO or PASS in addition to the measurement result.
Percentage deviation ( %)
This function enables the meter to display the percentage amount by which the reading differs from a nominal value chosen by the user. It is invaluable for measuring tolerance or stability.
Min-Max storage
The Min-Max function stores the highest and lowest values of a set of readings. This facility has many uses such as checking for power supply glitches and recording peak temperature excursions.
Power measurement in Watts or VA
In addition to dBs, power can be measured in Watts or VA. For resistive loads the Watts function calculates V2/R for any load resistance between 1W and 10kW, a particularly useful function for audio measurements.
Automatic data logging
The 1908 can store up to 500 readings at any required time interval from 1 reading per second up to 1 reading every 3 hours. A simple recall sequence allows the readings to be scrolled onto the display whenever required. Alternatively results can be downloaded using the remote interfaces. As a result, tedious time related measurement sequences can be handled automatically without disrupting your work. Manual storage of readings is also available eliminating the need for paper and pencil when making a series of measurements. Storage can also be triggered from an opto-isolated external trigger input, or from the digital interfaces.
External Triggering
An external trigger connector is provided on the rear panel. This provides for external triggering of measurement hold or measurement log. An opto-isolated open collector output is available for synchronisation with the measurement update.