TTi 1705 - 4 1/4 Digit LCD Multimeter

High Resolution and Accuracy

1705 is a 4¼ digit meter with a scale length of 12,000 counts and a resolution of 10μV, 10mΩ and 0.1μA. Combined with a high basic dcV accuracy of 0.04%, it provides measurements that are an order of magnitude better than most hand-held DMMs.
 

Closed Case Calibration

1705 stores its calibration constants in protected memory and can be recalibrated without ever opening the case.
 

Auto or Manual Ranging

1705 offers fully automatic ranging on all functions. Alternatively, ranges can be selected manually. Unlike other meters, the range value can be clearly shown on the secondary display avoiding any possibility of confusion.

1705 Series : Dual Measurement Bench Multimeter

Dual Display System

The 1705 has both a main display and a secondary display. The two displays can be used for a variety of purposes:

• To show the selected range in addition to the measurement units (e.g.100mAdc)
• To display a measurement in two different units (e.g. ac volts and dBm)
• To display the result of a calculated function (e.g. s 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)*

Mains or Battery Operation

1705 can operate either from ac mains or from batteries (disposable or rechargeable). In battery mode it can operate for up to 80 hours.
 

Dual Measurement

1705 can measure and display two signals simultaneously. These can be two parameters of one signal (e.g. ac volts & dc volts) or two signals applied to different sockets (e.g. ac volts & ac current).
 

Wide True RMS AC

1705 provides True RMS ac response which 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 and Capacitance

1705 offers high accuracy frequency measurement (better than 0.01%) from 10Hz to 120kHz. It uses a reciprocal counting technique to give up to 0.01Hz resolution at 10 readings per second. The 1705 also incorporates capacitance measurement in four ranges up to 120μF.
 

More Information

1705 has a number of powerful built-in functions designed to make life easier for the user. Most of these functions make use of the dual displays to provide extra information.
 

Tracking 'Hold'

The T-Hold function freezes the display every time a new but stable reading is detected. This avoids the problem of trying to watch the test points and the display simultaneously. Alternatively, a simple Hold function is also available.
 

Relative Measurement

The null function stores the current reading and subtracts it from future readings giving a 'relative' display. The nulled and normal readings can be viewed together. A separate Ω-null function retains an independent null value for resistance measurements enabling test lead resistance to be permanently nulled out.

Smart Functions for Added Power

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 any required impedance.
 

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.
 

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, recording peak temperature excursions and avoiding 'missed' readings when using the Logger function.
 

Power Measurement in Watts or VA

In addition to dBs, the 1705 can measure power in Watts or VA. For resistive loads the Watts function calculates V2/R for any load resistance between 1Ω and 10kΩ, a particularly useful function for audio measurements.

 
The VA function makes use of the dual measurement capability and displays the product of voltage and current.
 

Automatic Data Logging

The 1705 can store up to 100 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 RS232 or GPIB.

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 contact closure or the digital interfaces.
 

Full Bus Control via RS-232 or GPIB

The 1705 has an RS-232 interface as standard which can be used for remote control and read-back of measurements. As well as operating as a conventional RS-232 interface, it can also be used in addressable mode whereby up to 32 instruments can be linked to one PC serial port as part of a TTi 'ARC' system. A GPIB interface is available as an option.