Fluke 8842a External Trigger Timing Characteristics, Conversion Time ms 50 Hz 60 Hz 400 Hz

8842A

Instruction Manual

EXTERNAL TRIGGER TIMING CHARACTERISTICS

The following diagram shows the nominal timing for the various processes which take place between an external trigger and data sent out on the IEEE-488 interface. Delays will vary if a second trigger comes before the data handshake is complete.

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NOTES:	1.	Time for single trigger to start of A/D conversion.(See “Automatic Settling Time
		Delay” on previous page.) If the delay is disabled by using the T3 or T4 command,
		then the delay is 1 ms±150 μs. When the 8842A is triggered with an IEEE-488
		command (GET or ?), the automatic settling time delay begins after the trigger
		command has been processed and recognized.
	2.	A/D conversion time is dependent on the reading rate and power-line frequency:

RATE

A/D CONVERSION TIME (ms)

50 Hz

60 Hz

400 Hz

S

M

F

472(3800)*

52(960)*

7

395(3195)*

45(795)*

7

414(3300)*

47(840)*

7

*In 20 mV DC, 20Ω and 200 mA DC ranges.

3.Sample complete is a 2.5 μs pulse which indicates that the analog input may be changed for the next reading.

4.When talking to a fast controller.

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