Tip & How-To about Heating & Cooling

How a "Heater" or anything that has a "Load" works, & How to troubleshoot.

A Heater, is a real simple circuit. There are only TWO "Active" wires in any Electrical Circuit, the Phase, Positive, & Neutral, Negative, usually Negative & We also have an Earth, the Earth & Neutral are at the same, "Potential", IE:0 Volts. So imagine it like this, from the left we have a a Power wire, the Phase, this Wire, goes to One terminal on the On/Off Switch, this is called the "Hot" side, of this switch, This switch, when operated, "Breaks" the Phase line, or circuit, From the other terminal,the "Cold" side of the Power Switch, That wire, circuit, then goes from that "Cold" side of that switch, usually, to a "Thermal Fuse", wired in "Series" this "Fuse" is "Normally Closed", when/if, there is an "Overheating Condition", this "Device" will go "Open Circuit". Thus Breaking, the Phase Power, OFF, from the "Element", or "Load". Connection. This wire then goes, from the other terminal of that "Fuse" to the "Hot" side of the "Element". Now the other side or "Cold" side of the "Element" or "Load" then goes to "Neutral", or, return. Thus the circuit is now complete. Now the Earth, the MOST important wire, is bonded to the/any metal case &/or fittings of the unit, thus any "Hot" wire that may break, or touch, the "Earth" will cause a "Short Circuit" to Earth,and "Blow" the Circuit Breaker or Fuse on the Main Power Board. Thus affording protection from shock. Troubleshooting is simply following continuity along the circuit path, and the measuring of the On/Off components for integrity, and the/any "Fuses" and the "Resistance" of the Elements. This can be worked out from OHMS LAW, Volts = Amps multiplied by Resistance. Watts = Amps x Volts. From those two simple calculations we can glean the "Resistance" of the "Load" and what it should be. Then we can measure against that to see if there is any disparity, which would indicate the fault. EG: We have a heater it is 2000 Watts, it is in USA and the Voltage there is 120 Volts. First we must get our Current draw, we then divide the Wattage by the Voltage to get our Current draw. So, 2000 Watts, divided by 120 Volts, this equals, In our case, it is, 16.66 Amps. Now we know our Amps we can workout the Resistance of what our Elements will/should be. Now we Divide the Voltage by the Amperage to get this figure, in our case, 120 divided by 16.66 Amps, which is 7.2 OHMS, if there were 2 elements they would simply be 3.6 OHMS each, or any ratio of that. Now sometimes Heaters have a "Thermostat" this device is Powered from the Line, Phase, & Neutral, and using temperature sensing, it will act like a Switch, that is turned on & off, when a "Condition" Chosen Temperature, is met. It simply Breaks the Phase to the "Load". These "Contacts" are in series, with the Phase, and "Act" just like a/the Power Switch. Now in fault finding, we look for "Open" circuit where it should be "Closed" and "Closed" circuit where there should be "Open", also the "Resistance" of the "Elements" or "Load". So basically we are looking for, "Open" or "Short" circuits, and disparities of Resistance.. We remedy same by "Joining" up the "Break" or "Removing" the "Short" and replacing faulty "Loads" or "Elements".

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Is 50 volts of electrical ac current running on E line of an outlet can cause any disruption on the performance of a copier machine?

in a single phase circuit you have active (A) , neutral (N) and earth (E) or ground (G)
there is no voltage on an E terminal unless somewhere the system is incorrectly wired
suggest that you get an electrician in to check the circuits

Nov 27, 2016 | Motorcycles

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what is the common terminal on a device

If you are speaking of a light switch or an outlet it is white or chrome and the hot is brass in color

Apr 25, 2015 | Electrical Supplies

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www eemaxinc com support

My limited research indicates this heater is designed for USA electrical systems. That would mean single phase, 240/208 volts, 60 Hz. The drawings I reviewed shows a 2 pole, 240 volt breaker feeding each heating circuit. That means no "neutral wire" goes to the heater and therefore no 120 volts is needed. This is good. Kenya's system is single phase, 240 volts, 50 Hz. The heater should work reasonably well on the African system. Connect the power just like you would in the US.

Jan 17, 2014 | Water Heaters

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I need a simple wiring diagram to turn on 40 red leds and 40 green leds on a 9volt battery

Two ways to do it..........

One is a Series circuit, the other is a Parallel circuit.

Of course you can also use a Series/Parallel circuit.

Each LED has a Positive ( + ) connection, and a Negative ( - ) connection.

A) Series circuit:

One side of Switch is connected to Positive ( + ) of the Battery.
The other side goes to the Positive ( + ) of the first LED light.

Then the LED's are connected together in a Series.

Negative of first LED light to Positive of second LED light.
Negative of second LED light to Positive of third LED light.
Negative of third LED light to Positive of Fourth LED light.

And so on, and so on, until you come to No.40 LED light.
It's Negative connects to the Battery.

ONE LED goes bad, and none of them will work.
Old Christmas light strings are set up this way.

B) Parallel Circuit:

Switch to Battery - Positive ( + )
Wire goes from Switch, to 1st LED light's Positive connection ( + )
Then wire from 1st LED positive, to 2nd LED Positive ( + )
Then wire from 2nd LED Positive to 3rd LED Positive.

And so on, and so on, until you reach the 40th LED.

Then wire comes from Negative ( - ) of Battery, to Negative of 1st LED.
Wire from 1st LED to Negative of 2nd LED.
Wire from 2nd LED to Negative of 3rd LED.
Wire from 3rd LED to Negative of 4th LED.

And so on, and so on, until you reach 40th LED.
Wire connects to Negative of 40th LED. Then a wire connects from 40th LED Negative, and goes to Negative of Battery.


Series Circuit;


Over to the Left side you see the Battery symbol. There is no switch in this circuit.

In the Battery symbol, the Longer line represents the Positive pole.
(Positive connection)

Resistors are represented by the squiggly lines. In place of them put your LED lights.

A Switch would go in-between the Battery, and first LED light; on the Positive side.
(ALWAYS put the Switch on the Positive side. Can explain in detail if you need)

[The Top line in the diagram, is the Positive 'wire' ]


Parallel Circuit:


In a Parallel circuit, if one LED light goes out, the rest stay on.

For additional questions please post in a Comment.

Apr 12, 2013 | Computers & Internet

1 Answer

honda generator eb4000x gfic tripping

if you are using a lead that has a active , a neutral and a ground wire in the lead , there is no real reason to ground the gen set itself
the neutral will not be bonded to the frame as that would create a possible short during operation
the circuit is simple --active is the power wire --neutral is the return wire from the applications and the ground wire is for dead shorts and to prevent electrocution

Sep 09, 2017 | Honda Electrical Supplies

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