Fluke 2625A AC Signal Cross Talk Into an AC Voltage Channel, Ratio worst case, Ratio typical

2620A/2625A

Users Manual

AC Signal Cross Talk Into an AC Voltage Channel

ACV Error Ratio =

Range

⎡	VACrms(error)		⎤
⎢			⎥
⎣VACrms(crosstalk ) × Frequency(crosstalk ) ⎦
	Ratio (worst case)	Ratio (typical)

× ⎢

⎥ ×

⎢

⎥

× ⎢

⎥ ×

⎢

⎥

⎣v × Hz ⎦

⎣v ×

Hz ⎦

⎣v × Hz ⎦

⎣v

× Hz ⎦

30.000 V

1.2

× 10-6

⎢

⎥ 2.6

× 10-7

⎢

⎥

1.2 ×

⎣v ×

Hz ⎦

3.4 ×

⎣v

× Hz ⎦

150.00/300.00

10-5

⎢

⎥

10-6

⎢

⎥

⎣v × Hz ⎦

⎣v × Hz ⎦

For example, to find the typical effect of a 60 Hz, 220V ac signal on another channel for the 300 mV range, you would calculate: 220 X 60 X 1.4 X 10-8= 0.18 mV.

AC Signal Cross Talk Into an Ohms Channel

AC Frequency = 50, 60 Hz, ±0.1%

	1		⎡ Ohms(error) ⎤
OHMS Error Ratio		= ⎢			⎥
			⎣VACrms(crosstalk ) ⎦
Range				Ratio (worst case)			Ratio (typical)
⎡Ohms ⎤
× ⎢			⎥	3.0000 ke
⎣ Vrms ⎦				2.4 ×		×	30.000ke 3.1 × 10-

4 ⎡ kOhms ⎤

⎣

Vrms ⎦

⎣

Vrms ⎦

⎢

-5

⎡ kOhms⎥

⎤⎢

⎥

⎢

⎥

8.4 × 10

⎢

⎥

Vrms

⎣ Vrms

⎦

⎣

⎦

300.00 ke

5.6 × 10

-3

⎡ kOhms

⎤

3.7 × 10

-3⎡ kOhms ⎤

⎢

⎥

⎢

⎥

⎣

Vrms

⎦

⎣ Vrms

⎦

3.0000 Me

3.8 × 10

-4

⎡ MOhms ⎤

3.8 × 10

-5

⎡ MOhms ⎤

⎢

⎥

⎢

⎥

⎣

Vrms

⎦

⎣ Vrms

⎦

-3

⎡ MOhms ⎤

⎡ MOhms ⎤

10.000 Me

1.4 × 10

⎢

⎥

4.3 × ⎢

⎥

⎣

Vrms

⎦

⎣

Vrms ⎦

For example, to find the typical effect of a 60 Hz, 100V ac signal on another channel for the 30 kΩ range, you would calculate: 100 X 8.4 X 10-5 = 0.008 kΩ.

AC Signal Cross Talk Into a Frequency Channel

Frequency measurements are unaffected by cross talk as long as the voltage-frequency product is kept below the following limits:

Worst Case	Typical
V x Hz Product Limit	3.7 × 104 (V × Hz)	1.0 × 106 (V × Hz)

These values assume no more than 1000 pf of capacitance between either end of the resistor (HI and LOW ) and

earth ground.

D-2