Table 6-6: Gpib Addresses For Impedance Calibration - Ametek i Series User Manual

Table of Contents

User Manual

6.6.3 Output Impedance Calibration (3001iX, 5001iX, 9003iX, and 15003iX models only)

For the output impedance calibration, two HP 34401A DMM's or equivalent must be used. The

following modes must be programmed: 6 digits, AC Filter, slow: 3 Hz and 6 digits. One DMM is

used to measure the output voltage, one to measure the load current using a suitable CT. The

calibration should be done for each phase individually. Furthermore, an accurate phase meter

with at least 0.01° resolution is needed. (See equipment list section 6.1). The reference input of

the phase meter must be connected to the LOCK output of the controller at the rear panel of the

master 5001iX chassis. This is a square wave TTL signal. Select Square wave input on the

phase meter. The other input of the phase meter must be connected at the AC source output of

the phase being calibrated. Select Sine wave input on the phase meter for this input. Note that

this is a 230 Vrms signal so the Phase Meter must have sufficient input range on this input. The

phase meter is used to determine the phase shift between no load and full load conditions (

Connect the test equipment required as shown in Figure 6-2. If the DMM and phase meter have

an IEEE/GPIB interface, it is possible to use the 16-bit version of the CIGUI program version 3.18

or higher supplied on the CD ROM that came with the iX Series to operate the test equipment.

The 16-bit CIGUI requires a Windows 98 PC. (This function is not included in the 32 bit Cigui32

program however).

The calibration for impedance can be found in the Calibration Menu on the main CIGUI screen.

In this case, the GPIB interface must be connected to the PC, the DMM's and the Phase meter.

The GPIB addresses for the DMM's and Phase meter expected by the CIGUI program are

shown in the table below.

Instrument

iX AC Power Source

(Do not use 4,5 or 6 for AC source)

DMM1, Used for voltage measurement

DMM2, Used for current measurement

Phase Meter, Used for phase measurement

Note that the CIGUI32 (32 bit version) does not support computer aided impedance calibration.

Instead, the readings from the DMM's and Phase meter can be made manually and written

down. In that case, a calculator may be used to calculate the R and L portions of the impedance

using the formulas shown in Table 6-8.

To verify or adjust the programmable impedance function, proceed as follows for each phase:

1. Program the power source to 230.0VAC and 50Hz.

2. Program the output impedance resistance and inductance to the lowest values from the

OUTPUT IMPEDANCE screen. This will be the IMP. REAL MIN and IMP. REACT MIN

values that have been set in the OUTPUT CAL screen. Press the PHASE key to select the

phase to be calibrated. (A, B or C).

3. Measure the output voltage of the power source with no load and record this value (V

4. Using a resistive load bank, load the output of the power source to about 16 amps. Measure

the output voltage of the power source under load and record this value (V

the load current and record this value. (I).

i Series / iX Series