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Performance Tests
6
6-17
Verify that the returned value as shown on the Host screen = 255.
Note
The number returned is the decimal equivalent of the Digital Input binary
word (inputs 0 through 7’s status). See Table 6-7 to determine if the
number returned corresponds to the bits jumpered to ground in this test.
3. Jumper input 0 to ground by connecting the ground test lead to input 0’s test lead.
Then send the following command to Hydra Series II:
DIO_LEVELS? <CR>
Verify that the returned value as shown on the Host screen = 254.
4. Disconnect input 0 from ground then jumper input 1 to ground.
Send the command: DIO_LEVELS? <CR>
Verify the returned value is 253.
5. Repeat step 4 for each input and verify the correct returned value (See Table 6-7).
Table 6-7. Digital Input Values
TERMINAL GROUNDED STATE OF DIGITAL INPUTS DECIMAL VALUE
none inputs 0-7, all HIGH 255
0 inputs 1-7 HIGH, input 0 LOW 254
1 inputs 0,2-7 HIGH, input 1 LOW 253
2 inputs 0-1 and 3-7 HIGH, input 2 LOW 251
3 inputs 0-2 and 4-7 HIGH, input 3 LOW 247
4 inputs 0-3 and 5-7 HIGH, input 4 LOW 239
5 inputs 0-4 and 6-7 HIGH, input 5 LOW 223
6 inputs 0-5 and 7 HIGH, input 6 LOW 191
7 inputs 0-6 HIGH, input 7 LOW 127
Totalizer Test
This totalizer verification test requires toggling the Digital Output line 0 and using it as
the Total input. The test requires computer interfacing with a host (terminal or
computer). The host must send commands to the 2620A/2625A instrument to control the
digital line for this test. Refer to Chapter 4 for a description of configuring and operating
the Hydra Series II instrument.
1. Ensure that communication parameters (i.e., transmission mode, baud rate, parity,
and echo mode) on the Hydra Series II and the host are properly configured to send
and receive serial data. Refer to Chapter 4.
2. Switch OFF power to the instrument and disconnect all high voltage inputs.
3. Remove the Digital I/O ten terminal connector from the rear of the instrument and
all external connections to it. Connect short wires (to be used as test leads) to the 0
terminal and the Total (∑) terminal. Leave other ends of wires unconnected at this
time. Reinstall the connector.
4. Switch ON power to both Hydra Series II and the host.