更多"While paralleling two AC generators"的相关试题:
[单项选择]When paralleling two AC generators, the frequency of the machine coming on-line, immediately prior to closing its breaker, should be （）
A. slightly less than the oncoming generator frequency
B. the same as the bus frequency
C. slightly greater than the bus frequency
D. the same as the bus voltage
[单项选择]A position that is obtained by using two or more intersecting lines of position，taken at nearly the same time，is a(n)（）.
A. estimated position
B. fix
C. running fix
D. dead-reckoning position
[单项选择]You are attempting to parallel two AC generators, and the syncope pointer is revolving in the fast directionThis indicates that the frequency of the incoming machine is （）.
A. higher than the bus frequency
B. lower than the bus frequency
C. the same as the bus frequency but out of phase with it
D. the same as the bus frequency and the circuit breaker may be closed at any pointer position
[单项选择]You are attempting to parallel two AC generators and the synchroscope pointer is revolving in the slow directionThis indicates that the frequency of the incoming machine is （）.
A. higher than the bus frequency
B. lower than the bus freouencv
C. the same as the bus frequency but out of phase with it
D. the same as the bus frequency, and the circuit breaker may be closed at any pointer position
[单项选择]When two AC generators are being paralleled, the breaker should be closed with the synchroscope pointer mating in the （）
A. "slow" direction, just before the 12 o'clock position
B. "fast" direction, just after the 12 o'clock position
C. "fast" direction, just before the 12 o'clock position
D. "slow" direction, just after the 12 o'clock position
[单项选择]If two AC generators are to be operated in parallel, the load is distributed evenly by（）
A. means of rheostat the governor settings
B. a balance coil excitation
C. adjusting the governor settings
D. changing excitation
[单项选择]If two AC generators are operated in parallel, the load is distributed evenly by（）
A. a rheostat
B. a balancing coil
C. changing field excitation
D. adjusting the governor settings
[单项选择]The division of the kilowatt load between two AC generators operating in parallel is controlled by the settings and characteristics of the （）.
A. voltage regulators
B. field rheostats
C. reverse power relays
D. prime mover governors
[多项选择]Which two statements about using the CHAP authentication mechanism in a PPP link are true?（）
A. CHAP uses a two-way handshake
B. CHAP authentication periodically occurs after link establishment
C. CHAP has no protection from playback attacks
D. CHAP authentication is performed only upon link establishment
E. CHAP uses a three-way handshake
F. CHAP authentication passwords are sent in plaintext
[多项选择]Which two benefits are provided by using a hierarchical addressing network addressing scheme? （）
A. reduces routing table entries
B. auto-negotiation of media rates
C. efficient utilization of MAC addresses
D. dedicated communications between devices
E. ease of management and troubleshooting
[单项选择]When using the anchor to steady the bow while approaching a dock you must be aware of the fact that（）.
A. the vessel will tend to take a large sheer towards the side where the anchor is down
B. steering control is ineffective in trying to turn to the side opposite to that of the anchor being used
C. the anchor cable must never lead under the hull
D. using an offshore anchor decreases the chances of the anchor holding
[多项选择]What are two benefits of using NAT?（）
A. NAT protects network security because privat enetworks are not advertised.
B. NAT accelerates the routing process because no modifications are made on the packets.
C. Dynamic NAT facilitates connections from the outside of the network.
D. NAT facilitates end-to-end communication when IPsec is enable.
E. NAT eliminates the need to re-address all host that require extemal access.
F. NAT conserves addresses through host MAC-level multiplexing.
[多项选择]What are two benefits of using VTP in a switching environment?（）
A. It allows switches to read frame tags.
B. It allows ports to be assigned to VLANs automatically.
C. It maintains VLAN consistency across a switched network.
D. It allows frames from multiple VLANs to use a single interface.
E. It allows VLAN information to be automatically propagated throughout the switching environment.
[单项选择]Two vessels（）while they „re sailing in Huangpu River.
A. strike
B. strikes
C. are striking
D. struck
[单项选择]Two sites are using a multisite centralized call processing model. The voice gateway on the remote branch has lost IP connectivity to its Cisco CallManager server. Which feature enables the remote gateway to take the role of the call agent during the WAN failure？ （）
A. automated alternate routing （AAR）
B. Cisco CallManager Attendant Console
C. real-time protocol （RTP）
D. Survivable Remote Site Telephony （SRST）
[单项选择]At least two two-way VHF radiotelephone apparatus shall be provided on every cargo ship of（）tons gross tonnage and upwards but less than 500 tons gross tonnage.
A. 200
B. 300
C. 400
D. 800
