零线和地线连在一起

daocaoren

广东安规检测
有限公司提供：

小型摆管淋雨试验机

IPX5X6X7喷水试验机

1000L恒温恒湿箱

各种试验指现货

可程式恒温恒湿试验箱

水平垂直燃烧机

自动卷线器试验机

耐划痕试验机

各种灯头量规现货

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GB1002插头量规

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IEC61347/UL935镇流器热试验箱

灯具防风罩

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UL498插头插座量规

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家电125mm试验指

E12灯头量规

无绳壶无绳电熨斗插拔寿命试验机

IEC60335试验指甲

今天听到同事说美国的branch circuit 零线和地线是连在一起的，零线是没电的，
不知道有这么多学问，谁能告诉我真相啊.

fasten

这个要回到电工学了，理解一下电势的概念。

jsspace

LZ自己找资料学习以下几种接地保护方式吧
TN系统、IT系统。其中TN系统又分为TN-C、TN-S、TN-C-S系统。

billma

Step-by-Step Installation Process for a Secure and Safe Connection
Now the fun part: installing that 3-prong dryer cord yourself. Don’t worry — it’s not rocket science if you take it slow and follow these steps. Remember: always unplug your dryer from the power source before starting.
  i3 q# f% U- S1.Remove the Old Cord: Unscrew the panel on the back of your dryer where the cord attaches. You’ll see three screws holding the cord’s wires.
& u- R7 _( k! D2.Note the Existing Wiring: Take a picture or make a note of how the current cord is hooked up. The two outer wires are usually hot (live), the middle one is neutral.
3.Disconnect the Old Cord: Loosen the screws and remove the old cord wires from the terminals. Disconnect the bare ground wire if present.
4.Prepare Your New 3-Prong Cord: Strip the ends of the wires if needed to expose about ½ inch of copper.
" {+ e* b1 M" j1 |: N2 l5.Connect the Outer (Hot) Wires: Attach the left and right wires of the new cord to the outer terminals — usually brass screws. Tighten firmly.
6.Connect the Neutral (Middle) Wire: The middle wire connects to the center terminal, often a silver screw. But here’s the kicker — you need to attach the dryer’s metal frame to this neutral terminal to ground it properly. Usually, this means reconnecting a grounding strap or wire to the neutral terminal, bonding the frame and neutral together for safety on a 3-wire setup.
7.Secure the Cord: Use the strain relief clamp over the cord to hold it snugly, preventing any tension on the terminals.
1 U, ^& N/ s' o6 w" E8.Close the Panel: Screw the access panel back on tight, so no wires can be accidentally pulled loose.
9.Plug In and Test: Now, plug the dryer cord into your 3-prong wall outlet and power it on to test. You should hear the dryer hum to life without sparks or weird smells.
! q* d2 c5 z" X9 U  NRemember, the middle wire doubles as neutral and ground on a 3-prong setup, unlike newer 4-wire cords. It’s crucial to bond the dryer frame to the neutral terminal — skipping this is a common mistake that could create shock hazards.

billma

Step-by-Step Installation Process for a Secure and Safe Connection
7 Q  _  i% R$ KNow the fun part: installing that 3-prong dryer cord yourself. Don’t worry — it’s not rocket science if you take it slow and follow these steps. Remember: always unplug your dryer from the power source before starting.
1.Remove the Old Cord: Unscrew the panel on the back of your dryer where the cord attaches. You’ll see three screws holding the cord’s wires.
7 _4 O% d6 u# y) R2.Note the Existing Wiring: Take a picture or make a note of how the current cord is hooked up. The two outer wires are usually hot (live), the middle one is neutral.
3.Disconnect the Old Cord: Loosen the screws and remove the old cord wires from the terminals. Disconnect the bare ground wire if present.
4.Prepare Your New 3-Prong Cord: Strip the ends of the wires if needed to expose about ½ inch of copper.
! C5 B( [* B0 K& u" k5.Connect the Outer (Hot) Wires: Attach the left and right wires of the new cord to the outer terminals — usually brass screws. Tighten firmly.
6 K4 o% _* x) _" z0 U7 g6.Connect the Neutral (Middle) Wire: The middle wire connects to the center terminal, often a silver screw. But here’s the kicker — you need to attach the dryer’s metal frame to this neutral terminal to ground it properly. Usually, this means reconnecting a grounding strap or wire to the neutral terminal, bonding the frame and neutral together for safety on a 3-wire setup.
7.Secure the Cord: Use the strain relief clamp over the cord to hold it snugly, preventing any tension on the terminals.
8.Close the Panel: Screw the access panel back on tight, so no wires can be accidentally pulled loose.
9.Plug In and Test: Now, plug the dryer cord into your 3-prong wall outlet and power it on to test. You should hear the dryer hum to life without sparks or weird smells.
5 Q  C. q3 S* ZRemember, the middle wire doubles as neutral and ground on a 3-prong setup, unlike newer 4-wire cords. It’s crucial to bond the dryer frame to the neutral terminal — skipping this is a common mistake that could create shock hazards.

浪漫罗丹

感谢大牛分享 学习了