Fluke 2625A - Manual (Page 147)

Maintenance
Performance Tests
6
6-19
Hydra Series II’s display should now show the totalizing value incrementing at a 10
count per second rate.
Dedicated Alarm Output Test
The Dedicated Alarm Output Test verifies that Alarm Outputs 0 through 3 are
functioning properly. Because this test is dependent on voltage readings the Accuracy
Verification Test for channel 0 and the Channel Integrity Test for channels 1 through 3
should be performed if voltage readings are suspect.
1. Switch OFF power to the instrument and disconnect all high voltage inputs.
2. Remove the Alarm Output eight terminal connector module from the rear of Hydra
Series II and all external connections to it. Connect short wires (to be used as test
leads) to the ground (
J) and 0 through 3 terminals. Leave other ends of wires
unconnected at this time. Reinstall the connector.
3. Remove the Input Module from the rear of Hydra Series II. Open the Input Module
and jumper the H (high) terminal of channels 1, 2, and 3 together. Connect a test
lead to the H of channel 1. Also jumper the L (low) terminals of channel 1, 2, and 3
together. Connect a second test lead to the L of channel 1. Install the Input Module
back into Hydra Series II. Refer to Figure 6-4.
4. Switch power ON.
5. Using a digital multimeter (DMM), verify that alarm outputs 0 through 3 are in the
OFF or HIGH state. Perform this test by connecting the low or common of the
multimeter to the ground test lead and the high of the multimeter to the alarm output.
Verify a voltage greater than +3.8V dc.
6. Connect a cable from the Output VA HI and LO connectors of the 5700A to the V
Ω
and COM connectors on the front panel of Hydra Series II. Then jumper Hydra
Series II’s V
Ω
terminal to the H (high) test lead of the Input Module and the COM
terminal to the L (low) test lead (See Input Connection diagram).
7. On Hydra Series II, select the VDC function, 3V range, and assign a HI alarm limit
of +1.0000 for channels 0 through 3. Set up all other channels (4-20) to the OFF
function. Select a scan interval of 5 seconds.
8. Set the 5700A to output +0.9900 volts.
9. Press Hydra Series II’s SCAN button. Hydra Series II should scan channels 0
through 3 every 5 seconds.
10. Using a digital multimeter, again verify that alarm outputs 0 through 3 are in the
OFF or HIGH state.
11. Set the 5700A to output +1.1000 volts. Verify that the alarm outputs 0 through 3 are
in the ON or LOW state (measure less than +0.8V dc).