Explain clearance procedures starting from switching through grounding.
The request process, switching, issuance of the clearance, test the circuit, ground the circuit, explanation process, actual work, clearing of men, removing grounds, releasing clearance, and switching.
Name all forms involved in clearance.
260 clearance, 105 red tag, 182 switching.
Explain the rail return system. What would you need to work on it?
A combination of jumpers cables and impedance bonds that provide an electric path from train to substation. You need a jumper/Grounds.
What is a section break?
A point where 2 circuits are separated while providing continuous power.
What is a phase break?
A point where 2 power sources are separated.
What are the load dispatchers duties?
He Monitors and regulates power demands.
What are the power directors duties?
He is in charge of the power system within an assigned territory.
Prior to grounding transmission lines what steps must be taken?
Obtain power clearance and visually check the air break is open and ground switch is closed at the substation.
Grounds for caternary should be no less then what size cable?
Grounds for signal lines should be no less then what size cable?
What is an impedance bond?
A device that separates signal power from traction return.
What would occur if 1 leg of signal line would go to ground?
There would be a ground detected.
What would occur if both legs of signal line would go to ground?
The breaker would trip.
Name 4 things to check for while doing a substation inspection.
Targets, trolly voltage, battery voltage, and station ground.
What device would measure the flow of oil through cooling equipment on a transformer?
An oil flow gauge.
What is the difference between synchronous speed and full load speed of a motor?
Slip of the motor.
What are the ratings for our step down power transformers?
What are the ratings for our potential and service transformers?
Potential 200 va / service 50 va
Draw the configuration of an additive and a subtractive transformer.
H1. H2. H1. H2
X2. X1. X1. X2
Additive. / subtractive
What is control battery voltage?
132 - 140 volts. Dc
What do we use to charge the batteries in the substation?
When receiving a clearance on a bus section in a sub with only one potential transformer what must be done before receiving the clearance?
Switch power to other PT (power transformer)
What are the feeder breakers of the signal system?
What is the voltage and frequency of the 152 contactor ?
480 volts. 100 Hz
Ratio of output power to input power of a motor is what?
Describe the CR relay
Reverse current relay, trips the low side.
Describe the CA relay
Internal fault relay trips the low and the high side
Describe the CO balance
Line to ground relay, trips the low side
What is the JD what relay does it work with?
Timed relay that protects the bus, it works with the CA4 ( will trip the bus in 1.25 Sec if CA4 does not do its job)
What is a relay that operates in response to an expanding Bi metal?
Power transformers used by Amtrak are what configuration?
What are the primary and secondary voltages of a heater station?
Primary is 12 kv / secondary is 480 V
What is the main breaker of a heater station rated?
What are the secondary breakers rated?
What are Amtraks trolley breakers rated for?
What is a current transformer what does it do?
It provides current for the meters and relay equipment. It brings current down to a readable amperage.
What are the secondary wires of a CT what are the hot legs ?
F, ff. S, ss
What are the following relays? 27 and 230
27 is under voltage relay
230 is lockout relay
What is "A" contact?
Normally closed contact.
What is a rectifier?
It changes AC to DC
What is an inverter?
It changes DC to AC
Before working on a lightning arrestor what must be done?
Before working on a trolley breaker what must be done?
Discharge and remove DC
What is a megger how does it work?
An instrument that uses high voltage to test the insulation value of wires.
What is the Voltage and frequency of A 152 contactor?
480 Volts at 100 HZ
What allows the separation of trolley circuits and continuation of power?
The CR is supervised by what relay?
What does the 230 lockout relay prevent?
Auto closer of the feeder breaker.
What is the first thing you do if you get a hot tick?
Call the P. D.
What is the purpose of an impedance bond?
Separate signal power from track circuits.
At what voltage do you need a Clearance?
Anything above 480 Volts.
What is station control voltage?
132 volts DC.
What needs to be opened for a Transformer Clearance?
Low side first, then high side.
Amtrak’s step down (power) Transformers are what polarity?
What type of print is needed to replace or work on a test switch?
Relay and control print.
What is the rating of the primary fuse on a service Transformer?
. 5 amps
What is the ratio of a potential transformer?
How many volts and amps is a trolley breaker rated for.
3500 kv, 1500 amps
What alarm has a PD open the low side then the high side?
Bell temp alarm. B. T. A.
What is the acceptable Di - electric insulation value of oil (flash)?
26 and above.
How do you check voltage on a bus?
Meter at the potential fuse at the board.
A relay on a signal machine that begins with a 2 monitors what?
A relay on a signal machine that begins with a 1 monitors what?
What relays indicate a bus lock out?
What is the rating of a signal machine alternator?
How many amps are on the primary side of a step down Transformer under full load?
What transformer type has more turns on the secondary than on the primary?
Step up Transformer.
A relay that prevents or inhibits the automatic or remote function of a device?
Name the circuit property that exists when the relative position of 2 inductors cause the magnetic lines of force to link with the turns of the other?
Which transformer relay can operate the JD?
CR relay and the Backup CO relay.
A relay that has the properties of introducing a delayed action in which the delay decreases as the operating force increases?
Inverse Time Relay.
Name the device composed of 2 or more coils linked by magnetic lines of force that is used to transfer energy from one circuit to another?
The normal voltage for a 152 contactor circuit breaker?
480 Volts single phase.
The signal transformer at Amtrak are what polarity?
First thing you do when a circuit or equipment test energized after a Clearance has been issued?
Call the power director and follow his instructions.
A circuit is safe to work on only after you do what?
Grounds have been applied.
Before working on a Substation rail return bus you must do what?