Operator`s manual

Signametrics 120

iac ; IAC 3.3mA to 2.5A ranges, offset and gain

1.6 1.02402

0.0 1.03357

1.69 1.00513

0.0 1.0142

2w-ohm ; Ohms 33, 330, 3.3k,33k,330k,3.3M,33M,330Meg ranges, offset and gain

1.27e+4 1.002259

1256.0 1.002307

110.0 1.002665

0.0 1.006304

0.0 1.003066

0.0 1.001848

0.0 0.995664

0.0 1.00030

The first column under any function, e.g.,"vdc", is the offset term "b", expressed as a value proportional to

analog-to-digital (a/d) counts. The second column is the scale factor term "m". Within each function, the "b" and

"m" terms are listed with the lowest range at the beginning. For example, under "2

w-ohm" above, "1.27e+4

1.002259" represents the offset term for the 33 Ω range, and "1.002259" is the scale factor for this range. This

record must be for the SM2042 or SM2044 since the SM2040 does not have the 33 Ohms range, and therefore these

values will be set to 0.0 and 1.0.

For the ACV function, the first line in the calibration record is the DC offset value. The rest of the lines contain the

RMS offset, gain correction factor, and a third column that represents a digital code from 0 to 31 that controls the

high frequency performance of each AC function. A large value, e.g., 31, implies high attenuation.

The SM40CAL.DAT file is created by performing external calibration. The general calibration algorithm consists

of applying a zero value to the DMM followed by a value of 2/3

of the top of each range. Calibration of your

SM2040 is best performed using calibration software available from Signametrics.

When using multiple DMMs in a single chassis, the SM40CAL.DAT file must have a calibration record for each

DMM. You can combine the unique calibration records of each DMM into one SM40CAL.DAT file using any

ASCII text editor.