1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULApril 28, 20171UL 1247AOUTLINE OF INVESTIGATION FOR VARIABLE SPEED LIMITINGCONTROLS INSTALLED WITH DIESEL ENGINES FOR DRIVINGSTATIONARY FIRE PUMPSIssue No. 3April 28, 2017Summary of TopicsThis th
2、ird issue of Subject 1247A, Outline of Investigation for VariableSpeed Limiting Controls Installed With Diesel Engines for DrivingStationary Fire Pumps covers the construction and performancerequirements for a variable speed pressure limiting control (VSPLC) andvariable speed suction limiting contro
3、l (VSSLC) intended to be installedon a diesel engine for driving a stationary fire pump at the enginemanufacturing location. The minimum set pressure for a VSPLCreferenced in 6.17 has been reduced to 90 psig from 100 psig to providefor slightly lower pressures to be discharged into underground pipin
4、gwhich can have a pressure rating as low as 100 psig.ULs Outlines of Investigation are copyrighted by UL LLC. Neither a printed norelectronic copy of an Outline of Investigation should be altered in any way. All ofULs Outlines of Investigation and all copyrights, ownerships, and rights regardingthos
5、e Outlines of Investigation shall remain the sole and exclusive property of ULLLC.COPYRIGHT 2017 UL LLCUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULAPRIL 28, 2017UL 1247A2No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHE
6、R REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTS1 Scope .42 Components 43 Units of Measurement .44 Undated References 55 Glossary .56 Variable Speed Limiting Controls .57 Performance Tests 77.1 VSPLC Performance rating 77.2 VSSLC Performance test 87.3 Engine endurance at lowest opera
7、ting speed 87.4 VSPLC Operation test 97.5 VSSLC Operation test 97.6 Pressure Transducer (Sensor) Tests .107.7 Hydrostatic strength .127.8 Elastomeric parts (except gaskets) test 137.9 Cycling test .137.10 Contaminated water cycle test .147.11 Stress-corrosion cracking of brass parts test .147.12 Str
8、ess-corrosion cracking of stainless steel parts test .157.13 Deposit loading test 167.14 10-day corrosion test .168 Variable Speed Limiting Control Production Tests 179 Marking .18APRIL 28, 2017 UL 1247A 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSI
9、ON FROM UL1 Scope1.1 These requirements cover the construction and performance requirements for a variable speedpressure limiting control (VSPLC) and variable speed suction limiting control (VSSLC) intended to beinstalled on a diesel engine for driving a stationary fire pump at the engine manufactur
10、ing location. Inaddition to complying with the requirements described herein, the engine with VSPLC or VSSLC shallcomply with the applicable requirements of the Standard for Diesel Engines for Driving Stationary FirePumps, UL 1247.1.2 The engines covered by these requirements are intended for instal
11、lation and use in accordance withthe Standard for the Installation of Stationary Fire Pumps for Fire Protection, NFPA 20.2 Components2.1 Except as indicated in 2.2, a component of a product covered by this Outline of Investigation shallcomply with the requirements for that component.2.2 A component
12、is not required to comply with a specific requirement that:a) Involves a feature or characteristic not required in the application of the component in theproduct covered by this Outline of Investigation, orb) Is superseded by a requirement in this Outline of Investigation.2.3 A component shall be us
13、ed in accordance with its rating established for the intended conditions ofuse.2.4 Specific components are incomplete in construction features or restricted in performance capabilities.Such components are intended for use only under limited conditions, such as certain temperatures notexceeding speci
14、fied limits, and shall be used only under those specific conditions.3 Units of Measurement3.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory orapproximate information.APRIL 28, 2017UL 1247A4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION
15、ORDISTRIBUTION WITHOUT PERMISSION FROM UL4 Undated References4.1 Any undated reference to a code or standard appearing in the requirements of this Outline ofInvestigation shall be interpreted as referring to the latest edition of that code or standard.5 Glossary5.1 For the purpose of this outline of
16、 investigation, the following definitions apply.5.2 CORROSION-RESISTANT MATERIAL A material having resistance to corrosion equivalent to orexceeding that of a brass, bronze, monel, or series 300 stainless steel alloy.5.3 RATED PRESSURE The maximum working pressure intended for the device.5.4 SET PRE
17、SSURE The internal pressure at which a variable speed limiting control device isintended to begin to decrease engine speed.5.5 SYSTEM PRESSURE The pressure that is measured on the discharge side of the fire pump (theresult of the suction supply pressure, pump curve and engine speed droop) at any flo
18、w condition.5.6 VARIABLE SPEED PRESSURE LIMITING CONTROL (VSPLC) A factory installed engineattachment intended to limit system pressure by reducing the pump driver speed from rated speed.Where referenced in this standard, the VSPLC device is the primary variable speed control device thatis connected
19、 to the engine throttle or electronically controls the engine throttle.5.7 VARIABLE SPEED SUCTION LIMITING CONTROL (VSSLC) A factory installed engineattachment intended to maintain a minimum positive suction pressure by reducing the pump driverspeed from rated speed. Where referenced in this standar
20、d, the VSSLC device is the primary variablespeed control device that is connected to the engine throttle or electronically controls the engine throttle.6 Variable Speed Limiting Controls6.1 A VSPLC shall not decrease engine speed unless system pressure exceeds the set pressure.6.2 A VSSLC shall not
21、decrease engine speed unless the suction pressure drops below the set pressure.6.3 A VSPLC shall not increase engine speed above the rated speed for the purpose of increasingsystem pressure.6.4 A mechanical VSPLC or VSSLC shall be factory preset, and provided with a means such as afastening nut to s
22、ecure the intended setting and a tamper indicator such as a seal.6.5 An electronic VSPLC or VSSLC shall be factory preset and shall not be field programmable.6.6 A VSPLC or VSSLC shall be provided with a stop having a tamper indicator or other feature that willnot permit the engine to be operated at
23、 a speed below the lowest operating speed permitted by the enginemanufacturer.APRIL 28, 2017 UL 1247A 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL6.7 A VSPLC or VSSLC device shall be constructed for use at a rated pressure of at least 175
24、 psig (1.21Mpa).6.8 A part that bears against, rotates within, or slides on stationary parts, and that must be free to moveduring operation, shall be made of compatible corrosion-resistant material, or shall be fitted with bushings,inserts, or other parts made of these corrosion-resistant materials
25、at those points where freedom of motionis required.6.9 An interior bolt or screw shall be made of bronze or other corrosion-resistant material.6.10 An internal spring used in a VSPLC or VSSLC device shall be made of material having corrosionresistance equivalent to that of phosphor bronze and shall
26、not be susceptible to stress corrosion.6.11 Clearance shall be provided between working parts and between working and stationary parts sothat corrosion or deposits of foreign matter will not result in sluggish action or otherwise impairedoperation of the VSPLC or VSSLC device.6.12 If an orifice with
27、 a diameter less than 3/16 inch (4.8 mm) is used in operation of the device, a screenor strainer with corrosion resistance equivalent to brass shall be provided. The total area of the openingsin the screen or strainer shall be not less than 20 times the cross-section area of the opening that thescre
28、en or strainer is intended to protect. The largest dimension of the screen or strainer openings shallnot exceed 1/32 inch (0.8 mm) less than the diameter of the protected orifice.6.13 A VSPLC or VSSLC shall be provided with means to accept a 1/2 inch (12.7 mm) pipe for sensingpressure.6.14 A mechani
29、cal VSPLC or VSSLC device shall be constructed with a return spring or similar featuresuch that in the event of a failure of the pressure limiting control, the engine shall return to rated speed.6.15 An electronic VSPLC or VSSLC device shall be constructed such that in the event of a failure of thep
30、ressure limiting control, the engine shall return to rated speed.6.16 A pressure sensing line connected to a VSPLC or VSSLC device shall not incorporate a manualshutoff unless the shutoff valve has provisions to be locked in the open position.6.17 A VSPLC shall not have a set pressure less than 90 p
31、sig (0.62 Mpa).6.18 A VSSLC shall not have a set pressure less than 5 psig (34.5 kPa).6.19 A pressure-sensing device shall have a minimum orifice diameter of 1/8 inch (3.2 mm).6.20 A pressure transducer (sensor, transmitter) shall be field replaceable.6.21 An engine provided with a VSSLC shall be pr
32、ovided with a switch or means to activate alow-pressure signal when the suction pressure falls between 80 to 100 percent of the set pressure. Thesignal to the terminal and switch shall comply with the applicable requirements of the Standard for DieselEngines for Driving Stationary Fire Pumps, UL 124
33、7.APRIL 28, 2017UL 1247A6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7 Performance Tests7.1 VSPLC Performance rating7.1.1 When tested as specified in 7.1.2 7.1.6, a performance rating shall be established for the VSPLCand when subjected to
34、 these tests, a VSPLC shall begin to decrease the speed of the engine from ratedspeed with an inlet pressure at no less than 100 percent of the set pressure and no more than 105 percentof the set pressure.7.1.2 A mechanical VSPLC shall be tested at each set pressure and at least the minimum and maxi
35、mumspeed ratings.7.1.3 An electronic VSPLC shall be tested at least at the minimum and maximum set pressures and theminimum and maximum speed ratings.7.1.4 The VSPLC shall be attached to the engine such that it is operational. A stable inlet pressure, witha media of water, shall be created by means
36、of an external source and shall be plumbed to the inlet of theVSPLC device. If a positive displacement pump is used to establish the inlet pressure, dampers orsnubbers are to be used to stabilize the pressure.7.1.5 With the engine running and no load applied, inlet water pressure shall be applied to
37、 the VSPLCdevice starting at 90 percent of the set pressure. The inlet pressure shall then be gradually increased to115 percent of the set pressure or until the minimum engine speed has been achieved. Inlet waterpressure and engine speed shall be recorded.7.1.6 A VSPLC rating shall be established at
38、 each set pressure and representative engine speed ratingsbased upon the lowest VSPLC value achieved at:a) 110 percent of the set pressure;b) Rated pressure of the components intended for use with the engine; orc) The lowest operating speed permitted by the engine manufacturer using the followingcal
39、culation.VSPLC Rating,Z=1(N2)/(N1)2in which:Z is the rating of VSPLC. When the VSPLC is fully engaged, this is a value that is to bemultiplied by the maximum pressure on the corrected pump speed curve to obtain the maximumamount of trim pressure available using the VSPLC device;N1is the engine rated
40、 speed (RPM); andN2is the reduced engine speed (RPM).APRIL 28, 2017 UL 1247A 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7.2 VSSLC Performance test7.2.1 When tested as specified in 7.2.2 7.2.5, a VSSLC shall begin to decrease the speed of
41、 the enginefrom rated speed with an inlet pressure at no more than 100 percent of the set pressure and no less than95 percent of the set pressure.7.2.2 A mechanical VSSLC shall be tested at each set pressure and at least the minimum and maximumspeed ratings.7.2.3 An electronic VSSPLC shall be tested
42、 at least at the minimum and maximum set pressures and theminimum and maximum speed ratings.7.2.4 The VSSLC shall be attached to the engine such that it is operational. A stable inlet pressure, witha media of water, shall be created by means of an external source and shall be connected to the inlet
43、ofthe VSSLC device. If a positive displacement pump is used to establish the inlet pressure, dampers orsnubbers are to be used to stabilize pressure.7.2.5 With the engine running and no load applied, inlet water pressure shall be applied to the VSSLCdevice starting at 115 percent of the set pressure
44、. The inlet pressure shall then be gradually decreasedto 90 percent of the set pressure or until the minimum engine speed has been achieved. Inlet waterpressure and engine speed shall be recorded.7.3 Engine endurance at lowest operating speed7.3.1 An engine equipped with a VSPLC or VSSLC shall compl
45、y with 20.2 of UL 1247 and 7.3.2 when a1-hour endurance test is conducted at the lowest engine operating speed permitted by the enginemanufacturer.7.3.2 The endurance performance test shall be conducted per 20.2 of UL 1247 at the lowest operatingspeed and the maximum sustainable power output shall b
46、e no less than the power (HPL) determined asfollows:HPL=1.1*HPR*(NL/NR)3in which:HPLis the maximum sustainable power output required to be generated at the lowest operatingspeed permitted by the manufacturer as referenced in 7.3.1;HPRis the rated power at the lowest rated speed for a given engine mo
47、del;NRis the lowest rated speed for a given engine model; andNLis the lowest operating speed permitted by the engine manufacturer as referenced in 7.3.1.APRIL 28, 2017UL 1247A8UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL7.4 VSPLC Operation
48、 test7.4.1 When tested as specified in 7.4.3 through 7.4.5, a VSPLC shall maintain the system pressure suchthat within 5 seconds after the set pressure has been exceeded, the system pressure is to be maintainedat not less than 98 percent nor more than 110 percent of the set pressure. In addition, th
49、e systempressure shall be at least 98 percent of the set pressure within 20 seconds after the engine is started. Theengine speed shall return to the highest rated speed when the VSPLC is disabled.7.4.2 After 20 seconds from engine start-up, an electronic VSPLC shall maintain a stable systempressure such that the system pressure does not fluctuate more that 3 percent of the set pressure.Momentary pressure fluctuations outside the specified pressure band that do not last more than 3 secondsshall be permitted.7.4.3 A VSPLC shall be connected to an engine driven ce
