TM-9-2815-220-24 Maintenance Manual for AVDS-1790-2CA AVDS-1790-DA and AVDS-1790-2DR Engines Download

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TM 9-2815-220-24 FUEL/WATER SEPARATOR OPERATION TESTS 0042 00 WP 0042 00-7 TESTS (Continued) 3. Control unit test. UCAUTION Never touch a sensor probe to the positive terminal of the power source. Damage to equipment can occur. NOTE A red band identifies top sensor probe (high-level) and it is also the longer of the two probes. The lower probe is the low-level probe and is the shorter probe. a. With power supply connected, lightly press the tip of the low-level probe (15) to the negative (-) terminal of the 24-volt dc power supply. The voltmeter should register zero voltage. b. Continue holding the low level probe (15) onto the negative (-) terminal and at the same time press the tip of the high-level probe (14) onto the negative terminal. The voltmeter should now register 24 volts. c. Remove the high-level probe (14) only. The meter should continue to register 24 volts for 18 (± 3) seconds and then drop to zero volts. 14 15 Meter Negative Lead Meter Positive Lead