【正文】 The insulation resistance test shall be measured before the alternatingcurrent voltage test and after any directcurrent voltage tests.True 正確7. In according with the NEC, conductors and cables shall be durably marked on the surface of intervals not exceeding how many inches?a) 18 inches b) 24 inches c) 36 inches d) 48 inchesAnswer b) 24 inches 24 英寸8. TRUE OR FALSE: Metalcovered multiconductor cables shall employ a marker tape located within the cable an running for ist plete length, in lieu of cable surface marking.True 正確9. In accordance with the NEC which of the following colors would be permitted for an equipment grounding conductor?a) Black 黑色b) Green with a Yellow Stripe 綠色和一條黃色條紋c) White 白色d) Natural Gray 自然灰色e) Green 綠色Answer b) Green with a Yellow Stripe 綠色和一條黃色條紋 c) White 白色Page 10 of 61Questionnaire and Answer Sheet: INSTRUMENTATION 1 設(shè)備 11. What is the function of a barrier in an intrinsically safe circuit and how would you check for correct installation?Barrier safeguards hazardous area wiring and equipment against faults in the safe area. Check installation against drawings. Any divergence will invalidate . Certification.2. What is meant by a flameproof/explosion proof enclosure and what sort of information would you expect to find on a name plate attached to such an enclosure?An explosion proof enclosure is designed to contain an explosion such that escaping gases are incapable of igniting flammable mixture surrounding the enclosure.The device must be marked with manufacturer’s name, trademark, electrical ratings, Class an Group for which approved, ambient temperature or temperature code.In addition a name plate must be affixed carrying the following statement or an approved equivalent:CAUTION – to prevent ignition of hazardous atmospheres, disconnect the device from the supply circuit before opening. Keep assembly tightly closed when on operation.3. How would you check the alarm functions of an alarm annunciator? (Assume bare panel standing for test in a factory).Input two or more alarms in a related group and in sequence open contacts, acknowledge and determine if the first remains flashing.4. Explain what is meant by the functions AND, OR and NOT.AND output is ON only if all inputs are ON. OR output is ON if one or more inputs are ON. NOT output is ON if input is OFF and vice versa. 5. How would you check the calibration of a temperature recorder deriving its input from an external thermocouple?Use mV source and . tables. Applied mV=mV equivalent calibration equivalent of cold 溫度控制表。6. In what state are relay contacts shown on normal relay circuit diagrams?De energised (Shelf condition).7. How would you start a visual inspection of a control panel at a manufacturers premise? What are the salient points before starting detailed testing?Check the panel against . specifications, drawings and manufacturers standards, for pliance.8. What is meant by “first out” or “first alert” when applied to an annunciator sequence?First out feature is a means of identifying the first of a group of related or interactive alarm inputs to go into alarm state.9. In 1976, IEC Publication 529, Classification of Degrees of Protection provide by enclosures was issued. This document bines the requirements of IEC 144 which specifies degrees of protection for enclosures for low voltage switchgear and control gear with those of IEC Degrees of Protection by enclosures for rotating machinery.An enclosure defined by these standards could be marked by the letters IP followed by two digits. What is the significance of these two digits?1st digit – Protection provided against persons.　第一個(gè)數(shù)字：防止人體接觸。2nd digit – Protection against ingress of water.　第一個(gè)數(shù)字：防止雨水進(jìn)入。10. What markings would you expect to find on apparatus certified for use in potentially hazardous atmosphere under CENELEC standard EN 50018 (Flameproof enclosure ‘d’).EExdEuropean Electro technical Standardization Committee 歐洲電工技術(shù)標(biāo)準(zhǔn)化委員會(huì)Questionnaire and Answer Sheet: ROTATING EQUIPMENT 1 旋轉(zhuǎn)設(shè)備 11. What do you look for when inspecting fir tree slots in rotor discs of a gas turbine?The edges are rounded an there are no cracks.2. What do you consider a normal acceptable vibration limit for a large gas turbine (RPM 3 to 4 thousand)?.001” to .002” 英寸到 英寸3. How is the acceptance of fir tree dimensions of blades and rotor discs determined in a gas turbine?Plug gauge and / or optical parator.4. Is it necessary to clean the steam chest prior to running a steam turbine? If so why?Yes, otherwise nozzles and blading could be damaged.5. Name two methods of carrying out the NPSH (or suppression) test.Page 11 of 61? Vacuum tank, varying the liquid level of suction 、變化液體水平的吸入罐? Heat the water 加熱水? Throttle the 6. What roughness (surface finish) is required on the gear tooth surface?32 RMS or better on 90% of the tooth length as measured along the pitch line.7. After a pump is mounted on a base plate, what dimensions should be checked before shipping?? Anchor bolt hole ? Nozzle locations and 8. What types of tests / inspections / checks are usually made on centrifugal pumps?Material check, clearance checks, hydrostatic test, performance test, NPSH or suppression test, internal examination and dimensional examination.9. What is the minimum length of time the pressure should be held during the inert gas test of the casing?30 minutes. 30 分鐘10. How is the hydro test pressure determined for a pressor casing?. times the maximum design pressure for the casing.對(duì)于套管是 倍的最大設(shè)計(jì)壓力。Questionnaire and Answer Sheet: ROTATING EQUIPMENT 2 旋轉(zhuǎn)設(shè)備 2 1. What type of inspection and tests are usually made on centrifugal pumps?Mate