Fluke 2635A, 2625A Digital Input Test, Totalizer Test, Terminal Grounded, Decimal Value

HYDRA

Service Manual

Send the following commands to Hydra in sequence, and measure that the correct Digital Output line measures greater than +3.8V dc (HIGH state.)

DO_LEVEL 0,1 <CR>

Verify that output 0 measures a HIGH state.

DO_LEVEL 1,1 <CR>

Verify that output 1 measures a HIGH state.

Repeat the command for all eight outputs.

4-15. Digital Input Test

1.Perform the DIGITAL OUTPUT TEST steps 1 through 5.

2.Using either a terminal or a computer running a terminal emulation program, read the Hydra Digital Input lines.

Send the following command to Hydra: DIO_LEVELS? <CR>

Verify that the returned value is 255.

Note

The number returned is the decimal equivalent of the Digital Input binary word (status of inputs 0 through 7). See Table 4-7 to determine if the number returned corresponds to the inputs jumpered to ground in this test.

3.Jumper input 0 to ground by connecting the ground test lead to the input 0 test lead. Then send the following command to Hydra:

DIO_LEVELS? <CR>

Verify that the returned value is 254.

4.Disconnect input 0 from ground, then jumper input 1 to ground. Send the command: DIO_LEVELS? <CR>

Verify that the returned value is 253.

5.Repeat step 4 for each input and verify the correct returned value (See Table 4-7).

Terminal Grounded

none

0

1

2

3

4

5

6

7

Table 4-7. Digital Input Values

State of Digital Inputs

Inputs 0-7, all HIGH

Inputs 1-7 HIGH, input 0 LOW Inputs 0,2-7 HIGH, input 1 LOW Inputs 0-1 and 3-7 HIGH, input 2 LOW Inputs 0-2 and 4-7 HIGH, input 3 LOW Inputs 0-3 and 5-7 HIGH, input 4 LOW Inputs 0-4 and 6-7 HIGH, input 5 LOW Inputs 0-5 and 7 HIGH, input 6 LOW Inputs 0-6 HIGH, input 7 LOW

Decimal Value

255

254

253

251

247

239

223

191

127

4-16. Totalizer Test

This totalizer verification test requires toggling Digital Output line 0 and using it as the Totalizer input. The test requires computer interfacing with a host (terminal or

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