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13 Cards in this Set
- Front
- Back
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What is the purpose of the Test 30
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To ensure the proper operation of all track circuits and that the track relays are not over-energized in accordance with the C&S 996
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What types of Circuits are exempt from this Test?
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Electronic Circuits
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How often is the test 30 Done?
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When newly installed and then every 2 years there after
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what is the first step of this test?
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Take Relay readings
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What do you do next
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Polarity
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How is polarity done on DC and Type C Circuits?
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A DC volt meter will show the actual polarity of the circuit
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How is polarity done on an AC track Circuit
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place a shunt at least 500 ft from the relay end or opening the feed end fuses, Then you short out each I.J separately and observe the Relay if relay Vane drives back or against the stop polarity is satisfactory
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what if you are on an AC circuit without bonds ?
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both I.J's must be done simultaneously
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When is it not Necessary to Check Polarity ?
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1. on Single rail track circuit
2. A feed end adjoining a feed end 3. An AC track Circuit adjoining a DC track Circuit 4. 25hz track circuit adjoining a 100hz 5. A diode adjoining a diode track circuit |
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after you have done your polarity what is the next step you do?
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Shunt sensitivity
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How do you do the Shunt sensitivity test?
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place a shunt .06 ohms at both the relay and feed ends of the circuit individually
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what can we use as a substitute for the resistance box?
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15 ft of 16 AWG copper wire
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after you .06 the circuit whats the next step
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Check your A.S,C is properly adjusted
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