| Subject | Date Asked |
|
| Wiring for hot tub | 11/17/2009 |
Q: "I am installing a hot tub and the spa uses 30amps. From 60amp breaker in main panel (200amp ...
A: Jarrod... On it's face, yes. Provide seperate ground bars in the two sub-panels. Do not bond the ...
|
| 220 power | 11/12/2009 |
Q: I recently bought a British made recording console that uses two ac to multi-volt dc power supplies ...
A: Bill..... My guess is yes, it will work on your 208 or 240.....BUT....... I'm curious. In the photo, ...
|
| help? | 11/11/2009 |
Q: I'm a bit lost - on an electrical installation course and just trying to get ahead with some of the ...
A: A..... help me out here...... If the lamps are 110 volts, each lamp connected to one phase wire and ...
|
| electricmotor | 11/9/2009 |
Q: The wires from the motor are numbered just like on the wiring diagram, two of these wires are ...
A: Mark... Without a schematic, I can't tell you what color wire does what... However...... this motor ...
|
| Power to residence household | 11/9/2009 |
Q: I am interested in purchasing an electric deck oven to bake bread that uses 208/230+115 volts, 3 ...
A: Kathie..... The short answer is yes. 10-12 KW is about the same as your average electric range. ...
|
| Power to residence household | 11/8/2009 |
Q: I am interested in purchasing an electric deck oven to bake bread that uses 208/230+115 volts, 3 ...
A: Katie..... Unfortunately, 3 phase power typically is not available for residences. There are various ...
|
| electric motors | 11/6/2009 |
Q: I'm trying to hook up a Mill/Drill to 220v and using the reverse switch. sofar I have been able to ...
A: Mark.. The arrangement of wires coming from the motor determine the operating voltage and the ...
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| electric motors | 11/5/2009 |
Q: I'm trying to hook up a Mill/Drill to 220v and using the reverse switch. sofar I have been able to ...
A: Mark... After looking at the literature, it seems the wiring changes are confined to the numbered ...
|
| Low power in upstairs bathroom outlets | 10/19/2009 |
Q: Both of my upstairs power outlest in the bathrooms have low voltage, these are on the RCD circuit in ...
A: Nigel.. When you say RCD circuit, do you mean GFCI (ground fault circuit interrupter)? If this is ...
|
| Bad Breaker? | 10/9/2009 |
Q: I have had a 60 amp 2 pole breaker servicing an insta-hot HWH for 6 years. I recently serviced the ...
A: Paul....I think my earlier reply didn't get to you...... My money is on the insta-hot unit. Circuit ...
|
| 115/208 Hook up | 10/8/2009 |
Q: I have to hook up a food warming heater that was previously hard wired. THe data plate states ...
A: Jim...... This appliance is intended for use on a 208 volt circuit. The 115/208 label indicates the ...
|
| question about PSC motors | 10/8/2009 |
Q: i am a current HVAC SERV student at dunwoody college in minneapolis, minnesota. my teacher recently ...
A: Dom..... Whether or not a Split capacitor motor has an auto resetting or a manual resetting overload ...
|
| Bad Breaker? | 10/7/2009 |
Q: I have had a 60 amp 2 pole breaker servicing an insta-hot HWH for 6 years. I recently serviced the ...
A: Paul.... I doubt the breaker is bad, or ever was. You stated that you "serviced" the unit....what ...
|
| 2 x 120V not adding to 240V | 9/11/2009 |
Q: Good day, My hot tub is currently connected on my main electrical panel, via a GFCI box, on a 50 ...
A: Jon..... You didn't say what it DOES read.....really..... I'm assuming that you are taking ...
|
| low voltage | 9/10/2009 |
Q: my neighbor's boat lift is 200' from the source. 118volt at the lift. 3/4hp 13 amp motor. under load ...
A: Don..... Some thoughts, some questions.... While it's true that 8 volts drop is below the commonly ...
|
| transformer | 8/31/2009 |
Q: why delta connection has no neutral connection
A: Bala............ A "neutral" is a connection obtained by center tapping a transformer winding, ...
|
| Coils | 8/30/2009 |
Q: My question to you is how do I check a coil to see if it is bad? I have a mag starter for a 240 volt ...
A: Clint..... I'm going to assume that you've checked to see that there is the proper voltage present ...
|
| Generator Grounding | 8/29/2009 |
Q: I'm installing an 8 KW standby gernerator complete with transfer switch. The generator has a ...
A: Don.... Use of a ground rod is not required, nor is it a good idea. The generator transfer switch ...
|
| Armored Cable Sizing | 8/25/2009 |
Q: I am in the Mid East and we have a 275KVA Volvo Generator and this genset has a 400 amp main breaker ...
A: Dan... I need some data. I'm looking at cable sizes and allowable ampacities..... Tell me what the ...
|
| Power Supply to PLC | 8/16/2009 |
Q: Sir, Is ther any write up / reference standards about effects of low, high and interrupted power ...
A: Perhaps there are......PLC's are found in a plethera of devices. The effects of the conditions you ...
|
| HIGH TENSION POWER TRANSMISSION | 8/9/2009 |
Q: WHEN ONE OF THE WIRES OF A HT (220 KV ) TRANSMISSION LINE SNAPS AND FALLS, WHAT IS THE PROTCTION ...
A: Sudden changes in current, as when a line suddenly comes open, causes sensitive relays to react by ...
|
| Battery question | 8/4/2009 |
Q: I have a 1500 Amp-hour inverter battery used with a 1500VA power inverter. Recently, the summer heat ...
A: I doubt the minor overfilling did it. If the batteries have had sufficient time to charge and are ...
|
| Wiring for New Cooktop | 8/1/2009 |
Q: Robertson, I hired a contractor to update my kitchen, including installing a new gas cooktop which ...
A: Shelley... Sorry for the delay.....on a brief vacation. First.....electric cooktops almost always ...
|
| Battery question | 7/31/2009 |
Q: I have a 1500 Amp-hour inverter battery used with a 1500VA power inverter. Recently, the summer heat ...
A: 1.200 to 1.275 are acceptable readings, but don't necessarily tell the whole story. If all theses ...
|
| Battery question | 7/29/2009 |
Q: I have a 1500 Amp-hour inverter battery used with a 1500VA power inverter. Recently, the summer heat ...
A: Victor..... Your best bet is to talk either to the manufacturer of the inverter or the battery. ...
|
| wire size from weather head to panel | 7/28/2009 |
Q: I currently have a 400 amp 3 phase panel in a commercial building. I need to move the weather head ...
A: Eugene.... Whether or not the Service conductors need to be upsized for the additional lenght is ...
|
| Multipliers on Residential Electric Meters | 7/27/2009 |
Q: Why would a multiplier be applied to a residential electric bill? The electric bill contains columns ...
A: Natasha.... Most utilities have different rate schedules for different clases of service. If you are ...
|
| Distance from pedestal to house | 7/27/2009 |
Q: I'm building a cabin on an undeveloped, lake-side lot. There is road access, but it is quite a ...
A: I would use a 3/0, type USE aluminum triplexed cable, 24-30" burial depth. 100 amp. main at the ...
|
| Distance from pedestal to house | 7/26/2009 |
Q: I'm building a cabin on an undeveloped, lake-side lot. There is road access, but it is quite a ...
A: Greg... If I'm reading this right, the meter and service disconnect will be near the road, and a ...
|
| 277V to 120V | 7/24/2009 |
Q: I hope you are doing well. I was hoping to get your insight on another issue. I am proposing a ...
A: Matt.... First.... I got your lamp. I was impressed, to say the least.. I've been up to my eyeballs ...
|
| car alternator wire size | 7/23/2009 |
Q: I have an upgraded 400 watt alternator in my truck and am wanting it to run my 200 peak amp stereo ...
A: Seth.... 400 watts at 12 volts = 33+ Amperes. I assume you mean that the amp is 200 watts, not 200 ...
|
| Grounding my house | 7/23/2009 |
Q: I am converting from iron water piping to CPVC. The electricity in my home is grounded through my ...
A: Michael... The National Electrical Code forbids splicing the main grounding wire. You will have to ...
|
| Residential Transformer Box Noise | 7/22/2009 |
Q: SCE cahnged a 33 year-old residential transformer box twice. The second box is less noisy but can ...
A: Arming you with voluminous technical data would leave you where you are now.....at the mercy of the ...
|
| Grounding my house | 7/22/2009 |
Q: I am converting from iron water piping to CPVC. The electricity in my home is grounded through my ...
A: Michael... The important pipe is the one that brings the water into your house. The National ...
|
| electricity | 7/21/2009 |
Q: What's the opposite of "peak hours"? That's to say, the hours when electricity is cheaper? Many ...
A: Marimar.... "Peak hours" is a term usually used to describe a time period during the day when ...
|
| generator low output | 7/8/2009 |
Q: I have a 9.6kw gas Westerbeke on my houseboat. Recently I noticed a couple onboard devices not ...
A: Xavier... 9.6 KW gas is an older model. The generator is revolving field, brushless. There are ...
|
| switch for reversing motor | 7/7/2009 |
Q: Problem is...single phase,220 V.,5 HP motor to be used on a boat for pumping oil in and out of the ...
A: Terry...... I am going to assume that this device is portable, not fixed. As a rule, running ...
|
| Uniterruptable power supply | 7/6/2009 |
Q: I tried to power a tankless water heating device with UPS(BOSCH 2400, uses gas for heating and ...
A: Arif... A frequency inverter probably would work, but I believe the expense would be prohibitive. ...
|
| Residential Transformer Box Noise | 7/4/2009 |
Q: SCE cahnged a 33 year-old residential transformer box twice. The second box is less noisy but can ...
A: John... Never saw this follow-up. Noise from a transformer is a product of how its built and the ...
|
| 1ph load on 3ph power | 6/25/2009 |
Q: I have a standard (US) 480v 3ph power input. I want to provide power to a 480v 1ph resistance ...
A: Eric..... Using single phase loads on 3 phase systems is common. If your existing system has the ...
|
| IEC standard for termination | 6/22/2009 |
Q: Hai Robert Myself and one electrical inspector we together test a electrical panel. ...
A: sudhakar..... The IEC standards are very similar to our NEC 2005. As a general rule, one terminal, ...
|
| Track Lighting Voltage Question...HELP!!! | 6/21/2009 |
Q: First off, thank you for contributing to this site...I just stumbled upon it and it could be the ...
A: Matt... I have no problem with Juno products...have used them for years. I know of no reason why ...
|
| Track Lighting Voltage Question...HELP!!! | 6/17/2009 |
Q: First off, thank you for contributing to this site...I just stumbled upon it and it could be the ...
A: Matt.... The ratings applied to utilization equipment are MAXIMUM voltages and currents. I see no ...
|
| Grounding Panels | 6/11/2009 |
Q: I have two 200 amp disconnects at the pole with the meter box, and two 200 amp breaker boxes in two ...
A: William..... All the panels are required to be grounded. The two disconnects at the meter(service), ...
|
| Motor run capacitor | 6/8/2009 |
Q: I have a a/c fan motor which I replaced and I am replacing the 7.5 MFD capacitor. I have a brown ...
A: Bert.... I haven't serviced an A/C unit in years. Color coding is frequently ...
|
| Vacuum pump | 6/6/2009 |
Q: I have a vacuum pump that it suppose to be connect to 220 vac with only 4 wires with tag t1 t2 t3 t4 ...
A: Yves..... Found lots of info on Surge, but no specifics,,, If you can get your hands on a continuity ...
|
| Hood exhaust & return air switch (single) | 6/6/2009 |
Q: I have two exhaust fans and one return air hood system and they come with three separate two speed ...
A: Dan..... It's possible the manufacturer of your equipment has an arrangement to simultaneously ...
|
| Whirlpool tub | 6/4/2009 |
Q: I just bought a Lasco Whirlpool tub and the electrical installaton instructions say that some states ...
A: Chris... The State of Ohio has adopted the 2008 National Electrical code as part of it's residential ...
|
| Overvoltage from genset | 6/4/2009 |
Q: I have an older Kohler 5500W genset. It works and runs great, but puts out 145V on my digital ...
A: Glenn; I doubt that the overvoltage you see will do much harm. Most of the portable motor-gen sets ...
|
| Screw through wire | 6/3/2009 |
Q: I was preparing the drywall in my garage and noticed a screw about a foot above my electrical panel ...
A: You need only replace that part of the cable that is damaged. A junction box is required. At least 6 ...
|
| running wire from house to garage | 5/29/2009 |
Q: running wire from house to garage what gauge wire should i use i will be running an air compressor ...
A: The size of the wire used is dependent on the total amperes it will carry. Check the nameplate on ...
|
| moving my breaker panel | 5/29/2009 |
Q: I need to move my breaker panel from the back of the house to the front of the house due to a ...
A: Ridgid, non-metalic conduit, listed for direct burial, and appropriate fittings, may be used. This ...
|
| moving my breaker panel | 5/28/2009 |
Q: I need to move my breaker panel from the back of the house to the front of the house due to a ...
A: The allowable length of service entrance conductors inside a building, ahead of the first ...
|
| Dayton Generator Model 3W056B | 5/27/2009 |
Q: Do you have any idea when this model was built and where we can get a manual and wiring diagram? ...
A: Judy..... I looked in all my favorite places for info on this plant. No owner's manuals to be ...
|
| 3 phase 480 | 5/27/2009 |
Q: I'm reading 374v on "A" and "B" phase, and 70v on "C" phase on the primary side of the xfmr. The ...
A: If the primary voltages were read correctly, the loads on the secondary could not have operated ...
|
| 3 phase 480 | 5/25/2009 |
Q: I'm reading 374v on "A" and "B" phase, and 70v on "C" phase on the primary side of the xfmr. The ...
A: Hmmmmm....... Questions.... What prompted you to take voltage measurements? Is the 480 system wye ...
|
| 240 volt single phase motoer | 5/25/2009 |
Q: I recently purchased a table saw that has a 240 volt single phase motor. After installing a new ...
A: From what I can glean from the doucments, the switch is a mechanically latched device, not an ...
|
| 240 volt single phase motoer | 5/25/2009 |
Q: I recently purchased a table saw that has a 240 volt single phase motor. After installing a new ...
A: Tristan.... Send me the make and model of the saw.....it sounds like the control circuit isn't ...
|
| Switching requirements | 5/24/2009 |
Q: Good day and thank you for considering my question. I have been working at a location and the ...
A: Moira..... The NEC has no position on how many switches should be used for any given lighting ...
|
| reverse power for alternators | 5/21/2009 |
Q: How reverse power produced in power generation?1300 kw,3 phase,1200 rpm,6 pole,60 HZ Alternator how ...
A: I don't think it's really negative or reverse power...it may be that the current transformers used ...
|
| Transformer installation standard | 5/21/2009 |
Q: 5000 KVA air forced dry type transforemer installed in a room.what is the standard clearance between ...
A: sudhakar...... the best source of info will be that supplied by the manufacturer of the transformer. ...
|
| Transformer installation standard | 5/20/2009 |
Q: 5000 KVA air forced dry type transforemer installed in a room.what is the standard clearance between ...
A: Sudhakar... In the U.S., The National Electrical Code sets the requirements for the installation of ...
|
| voltmeter principle | 5/20/2009 |
Q: how the anolog and digital voltmeter works ?
A: Sudhakar.... Most analog voltmeters use a magnet/coil- type meter with a resistance in series to ...
|
| reverse power for motors | 5/18/2009 |
Q: hai robert i am working in jackup oil Rig.The jacking motor specifications- squrrial cage induction ...
A: Sudhakar... I'm not sure what is happening....How is this reverse power showing up? What effect is ...
|
| Electrical | 5/18/2009 |
Q: Hai Rober, what is IP rating for motors? If the motor name plate mention the IP 65 means ...
A: Sudhakar.. IP ratings are a measure of how well the motor is suited for the environment it is ...
|
| half of my apartment lost electricity | 5/18/2009 |
Q: Yesterday half of my apartment (bedroom and bathroom) suddenly lost electricity but the living room ...
A: Rita...... If you are a renter, this is not your problem. Notify your landlord immediately. There ...
|
| Under Ground Wiring | 5/16/2009 |
Q: We have a cottage and there was a power connection buried that runs to the boat house to supply ...
A: Karl...... I'm not sure what kind of tester you're using. but it sounds like the repair made to the ...
|
| 2 foot rule in Arizona kitchen renovation | 5/15/2009 |
Q: We are installing new cabinets and a higher counter top on one wall in our kitchen (up from ...
A: Doris..... In Arizona, building codes are adopted by each individual municipality. My guess is that ...
|
| sensing AC | 5/15/2009 |
Q: There are noncontact sensors for detecting/measuring AC current in a power cable under load (with a ...
A: Gene... Non-contact AC voltage sensors are common. I use a shirt-pocket tester made by Fluke. It is ...
|
| Light Problems | 5/14/2009 |
Q: . i replaced a light fixture in my hallway and when i turned the breaker back on that light didnt ...
A: Jeff..... Could be something simple like when you reconnected the wires together, one of them came ...
|
| Circuit Breaker Panels | 5/12/2009 |
Q: Is there a law/regulation in PA against having a Zinsco Circuit Breaker panel?
A: Pete...... Pennsylvania has adopted the ICC 2006 construction codes. The ICC electrical code is ...
|
| re-installing a temporary pole | 5/10/2009 |
Q: The breaker box on our temporary pole, that we have had set-up for quite some time had shorted out. ...
A: Utility companies seal metering equipment primarily to deter tampering and power theft. In your case ...
|
| pvc/swa/pvc | 5/9/2009 |
Q: Good Day sir, I would like to ask about L.V power cable using for 3 phase laying underground to ...
A: PVC insulated, steel wire armored, PVC bedded cable is acceptable for use underground in wet ...
|
| Boat hoist/drum switch problems | 5/8/2009 |
Q: I have an overhead boat hoist which utilizes a Century 3/4 hp motor. I broke the handle off the ...
A: Greg....if you only "hummed" the motor for a brief time, I doubt you did it any harm. I'm going to ...
|
| Too much voltage | 5/7/2009 |
Q: What is the maximum allowable voltage for home service? What I mean is my A/C compressor, espresso ...
A: Robert... Some comments: Distribution transformers of any age work or they don't work. When they ...
|
| Too much voltage | 5/6/2009 |
Q: What is the maximum allowable voltage for home service? What I mean is my A/C compressor, espresso ...
A: Robert... In Illinois, voltages delivered by utilities to their customers are regulated by the ...
|
| Motor reversal by relay control | 5/4/2009 |
Q: I have a Dayton gear motor (Grainger # 1LPV1). Motor leads CW white, purple, red to common and ...
A: Yes. I've attached a sketch. Do not use this circuit to stop and start the motor. The motor ...
|
| Elec. Engineering-Short circuit calculation. | 5/4/2009 |
Q: Sir, I wish to get a detailed answer for 1.what is short circuit in Electrical Engineering? 2.why ...
A: Subhash........ Not being an engineer, I can't give you specific formulas for calculating short ...
|
| Plug-top transformers | 5/2/2009 |
Q: I was wondering, how to plug-top transformers (phone chargers, for example) or laptop PSUs accept ...
A: David.... In the U.S. we call those devices "wall warts". There are a number of ways to reduce line ...
|
| 480/240 transformer | 5/1/2009 |
Q: I am installing a 480 to 240 3phase transformer.please let me know if i am incorrect in my ...
A: Pete....... Yes, it should. In all cases, the manufacturer's instructions rule. You should ...
|
| Dimmer for low voltage lights | 4/29/2009 |
Q: the electronic dimmer controlling my low voltage track lights cause buzzing in the light bodies ...
A: Petra...... Where the transformer is located in the circuit has nothing to do with anything. ...
|
| Dimmer for low voltage lights | 4/28/2009 |
Q: the electronic dimmer controlling my low voltage track lights cause buzzing in the light bodies ...
A: Petra...... There are two kinds of transformers for low voltage fixtures....magnetic and ...
|
| single phase motors | 4/27/2009 |
Q: can a single phase motor rotate in either direction from one supply without altering connections at ...
A: Unlike 3 phase motors, single phase motors cannot be reversed simply by flipping the lines. However, ...
|
| Voltage transformer issue | 4/26/2009 |
Q: I have a voltage transformer from 11volts to 220 for my european appliances. I don't understand the ...
A: On it's face, it sounds like you're mixing equipment intended for use on grounded systems with ...
|
| what causes voltage on a neutral line | 4/24/2009 |
Q: Our dishwasher control board burnt up. The repair man installed a new board and it burnt up ...
A: The neutral is open or intermittent between the dishwasher and the circuit breaker panel. While it ...
|
| AC polarity | 4/22/2009 |
Q: Sir, What are some of the reasons the NEC enforced the need to maintain polarity in AC circuits?
A: AC systems are not "polarized" in the true sense of the word, in that there is no consistantly ...
|
| difference in frequency | 4/22/2009 |
Q: Sir, I wish to know that if any electrical item designed for work at 60Hz try to work with 50Hz (at ...
A: Subhash...... The silly question is the one not asked. Purely resistive loads(toasters, irons, ...
|
| European 220v vs. American 220 | 4/21/2009 |
Q: I believe that in Europe our 220v is 1 phase and that in the US 220v is 2 phases (2 110v hot wires). ...
A: 220 volts is 220 volts is 220 volts. In the U.S. the power supplied to most residences is 120/240 ...
|
| difference in frequency | 4/20/2009 |
Q: Sir, I wish to know that if any electrical item designed for work at 60Hz try to work with 50Hz (at ...
A: The heating element of the heater will be fine.....the fan motor will run approx. 20% slower, and ...
|
| difference in frequency | 4/20/2009 |
Q: Sir, I wish to know that if any electrical item designed for work at 60Hz try to work with 50Hz (at ...
A: The theory of operation of ground fault detection/relay equipment is uniform. The devices look for ...
|
| difference in frequency | 4/19/2009 |
Q: Sir, I wish to know that if any electrical item designed for work at 60Hz try to work with 50Hz (at ...
A: Subash........ There is no single answer to your question. There is a great deal of electrical and ...
|
| Electric motor conversion to 220 volt operation | 4/18/2009 |
Q: Can you explain to me the benefit of converting my table saw and band saw motors to 220 volt? ...
A: It's your imagination. Motor speed is primarily dependant on the number of poles in the motor and ...
|
| Electric motor conversion to 220 volt operation | 4/18/2009 |
Q: Can you explain to me the benefit of converting my table saw and band saw motors to 220 volt?
A: John..... Interesting question. There is a myth out there that running stuff on 240 volts is ...
|
| failure of GFI resulting in electrocution | 4/16/2009 |
Q: Can a Ground Fault Interrupter (GFI) fail such that the circuit could stay live during a ground ...
A: GFCI's fail all the time. A class 'A' GFCI should trip when imbalance exceeds 20 milliamps. If the ...
|
| Beck's Neon sign | 4/14/2009 |
Q: Its broken, the glass tube and part is missing. However the green "Beck"s" part still lights up, ...
A: Paul...... Understanding capacitance and electrostatics and yadda yadda is difficult without ...
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| Beck's Neon sign | 4/13/2009 |
Q: Its broken, the glass tube and part is missing. However the green "Beck"s" part still lights up, ...
A: I would avoid touching the wire.....neon sign voltages can be very high. The electrical activity in ...
|
| Home Generator | 4/12/2009 |
Q: A friend of mine has a Hondaline ES4500 Generator that he wants to hook up to use as a back up ...
A: So, the switching /hook-up device has a 4-wire inlet(male receptacle) OK. It shouldn't be that hard ...
|
| Beck's Neon sign | 4/12/2009 |
Q: Its broken, the glass tube and part is missing. However the green "Beck"s" part still lights up, ...
A: Paul...sorry for the delay....your e-mail went to my spam file. The devices could be neon or some ...
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| Beck's Neon sign | 4/11/2009 |
Q: Its broken, the glass tube and part is missing. However the green "Beck"s" part still lights up, ...
A: So, how do you like being a human capacitor? It sounds like the "broken" part still has gas in it ...
|
| Home Generator | 4/10/2009 |
Q: A friend of mine has a Hondaline ES4500 Generator that he wants to hook up to use as a back up ...
A: Without seeing the literature for this unit, I offer the following possibilities: I assume that ...
|
| sub-woofer | 4/10/2009 |
Q: I have a monster cable god father sub-woofer 1000watts (15 amp. fuse)110VAC 60 hz.but in my country ...
A: Amplified sub-woofers have solid-state power supplies....usually a transformer and some arrangement ...
|
| Electrical Safety | 4/9/2009 |
Q: I am a safety consultant using NFPA 70e but not an electrician. How does one safety identify ...
A: Eugene....... There is no one single answer.The level of identification of electrical equipment may ...
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