PDX DCEO Qualification Card

Discuss the following with regard to the switchgear HMI/AMCOP: Discuss what happens if both main line power sources are lost to the switchgear HMI/AMCOP

AMCOP will enter an Auto Fail condition. A Deadbus timer will start. If supply power has not been restored once the timer is complete (90 seconds) the ATC (Woodward) will transition so load is provided via 480V Catcher.

Discuss the following with regard to the switchgear HMI/AMCOP: List the components that interface with the switchgear HMI/AMCOP

Associated MCBU, MCBG, generator, utility Basler, generator Basler, and BMS.

Discuss the following with regard to the switchgear HMI/AMCOP: List the power supplies for the switchgear HMI/AMCOP

HPP, HUPP/CUPP, internal battery

Discuss the following with regard to the switchgear HMI/AMCOP: What busses do the basler relays monitor?

Upstream of MCBU and MCBG (Utility and Generator busways)

Discuss the following with regard to the switchgear HMI/AMCOP: What is the difference between the basler relays and the interposing relays?

A basler relay is considered the "eyes" for the PLC, they look for anomalies and notify the PLC. The Interposing relays are considered "the hands" for the PLC, they are used to carry out automatic functions as dictated by the PLC.

Discuss the reasons for long time, short time, instantaneous, and ground fault settings

Long: Overload Protection

Short: Delayed short-circuit Protection

Instantaneous: Instant short-circuit Protection

Ground Fault: Short-circuit to ground protection

During an Emergency can you perform breaker manipulation by yourself?

Yes, but it is not recommended.  Use EOP and escalate.

Explain how power is distributed from medium voltage transformer to the rack.

MV XFMR > USB (MCBU) > CDB (CDB Main > MIB) > UPS > MOB > IOB > PDP XFMR > PDP > PDU > ATS > Rack

Explain the controls inside the power distribution cabinet (PDC).

PDCs contain the following: surge and short circuit protection devices to protect downstream WMW racks. Meters for monitoring cabinet current, power, temperature, and line to line voltage. Redundant internal device power supply. BACOP integration units.

Explain the different breaker rack out positions (connected, test, disconnected, and withdrawn)

Connected: Power (Primary), Control (Secondary/Auxiliary) circuits, and ground are connected, breaker is racked in and fully operational.

Test: Power (Primary) circuit is disconnected with Control (Secondary/Auxiliary) circuit and ground connected, breaker is operational for offline testing and safety.

Disconnected: Power (Primary), Control (Secondary/Auxiliary) circuits are disconnected, ground is connected. Breaker is partially racked out offline.

Withdrawn: Power (Primary), Control (Secondary/Auxiliary) circuits, and ground are disconnected, breaker is fully racked out and offline.

Explain what happens when the MCBG breaker trips with the Generator supplying all loads.

AMCOP will enter an Auto Fail condition. A Deadbus timer will start. If supply power has not been restored once the timer is complete (90 seconds) the ATC (Woodward) will transition so load is provided via 480V Catcher.

Explain why we have a coordination study performed for our electrical distribution system.

Coordination studies are useful for determining selective tripping guidelines. This provides the ability to sequentially trip loading on the lowest possible levels and limit adjacent customer impact.

How do you perform an OPTDC USB to Catcher Tie?

Rack out/disconnect MCBU and MCBG, complete a deadbus timer, use SKRU key to close MCBC

How does the backstopping system (BACOP) work?

BACOP senses busway loading and preemptively sheds loading selectively to protect critical loads and circuit breakers.

How does the FLoRES work?

FLoReS communicates between adjacent protection relays in loops to automatically isolate electrical faults within 5-10 cycles and restore voltage to the unaffected sections within seconds. Fault indication is via 2 Feeder Protection Relays or 1 Transformer Protection Relay.

How is a breaker trip indicated?

Local indicator and EPMS.

How long can the Critical Uninterruptible Power Supply (CUPS) supply its loads while on battery?

Depends on loading. Average loading (<10%) is in excess of 60 minutes. PDX4 is roughly 6-12 minutes.

If a utility outage were to occur, explain how the 6A lineup would respond.

Customer load is carried via UPS batteries (non-WMW) or powershelf batteries (WMW). WMW sites will additionally use UPS batteries to power mechanical loads. Basler relays detect a loss of utility. After 3 seconds, the utility breaker opens and the generator is started. After a 12 second (5 seconds for WMW sites) stabilization delay, the generator breaker is closed and the generator supports customer load.

In relation to the ATC what does TDNE and TDEN stand for?

TDNE = Time delay normal to emergency.  TDEN = Time delay emergency to normal.

List the control power sources for the USB and PDP

Utility, Generator, HUPP and associated UPS.

OPTDC: Utility, Generator, CUPP A, and CUPP B,