HVAC Learning/training Dvds

[moondawn]

Hi there,

Has Anyone got any training Dvds on HVAC If so Please could someone help out am willing to pay money for these to help me out with my training?

[Latte]

Dont know of any dvd/video training methods but you may want to have a look at :-
http://www.kotza-international.com/site/gb/climeaudep.html

VERY good computer training, everyone that i know who has seen it rates it highly

Hope this helps

Regards

Latte

[moondawn]

thanks for the reply, will look into that too
many thanks

[frank]

Dont know of any dvd/video training methods but you may want to have a look at :-
http://www.kotza-international.com/site/gb/climeaudep.html

VERY good computer training, everyone that i know who has seen it rates it highly

Hope this helps

Regards

Latte
What do you make of Question 4?


Q.4
If there is a voltage measured between the terminals of an electrical contact, then this confirms that the contact is open.
True
False

[Latte]

Which one are you doing Frank ?

Sorry all, not the best of links £200 !!!!!!!!!!!!!!!!!!!!!!!!, although there is a couple of quiz's in the quiz section to have a look at on the website

good software, ok if a company is going to buy it for ongoing training but a bit over the top if you are buying it personally

Must find my CD i got from RAC all those years back

Regards

Latte.

PS, Cant find a Daikin section ;)

[frank]

Just looking through a few questions...........

From my perspective, if you are measuring a voltage then you must have one lead of you meter touching neutral or earth. The other lead touches one side of the open contact and you see a voltage, then on the other side you don't. If you see a voltage on both sides of the contact then the contact is made (closed)

Try answering the question and see what you get????????

Maybe they measure things differently in the US, or the questions are aimed at something other than electrics? Confused - you bet.

[Latte]

just had a thought (Dont mock, its 9pm and ive got to up at 5am to go to Lakeside), going slightly off topic, but does normally open and normally closed mean the same both sides of the pond. Only reason i ask is because of Franks question footnote. I seem to remember coming accross this before where we put an answer but they are looking for the opposite answer.

Is it a terminology thing, for instance i have always called a thermostatic expansion valve as a TEV, however whilst in America a couple of months ago everyone called it a TXV.

Regards

Latte

[Brian_UK]

The difference between the test methods is what is confusing folks here I think.

You will often find instructions to test if a switch is open or closed by connecting your test meter leads to both sides (contacts) of a switch (not a single point and earth).

In this type of test if the switch is closed, contacts made, then there will not be a voltage across the contacts.

If the switch is open , contacts broken, then there will be a voltage across the contact because the voltage is going through the meter.

[Moris]

The term normally open N/O this side of the pond means as the item (contactor relay etc) is taken out of the box, which ever position the contacts are in is there state ie. un-powered state. In America it is the opposite as their schematics are drawn as powered on and ours are drawn as power off.

hope this helps

[RatsPom]

What do you make of Question 4?


Q.4
If there is a voltage measured between the terminals of an electrical contact, then this confirms that the contact is open.
True
False

True, because you are measuring the potential difference in the circuit between 2 contacts.

If you place the 2 probes of a volt meter on a single piece of wire with a voltage running through the wire then you will not measure a voltage if however you (as in Q4) you place the probes between the terminals of an open contact then you will measure voltage due to the difference in potential between both terminals of the open contact

[frank]

True, because you are measuring the potential difference in the circuit between 2 contacts.

If you place the 2 probes of a volt meter on a single piece of wire with a voltage running through the wire then you will not measure a voltage if however you (as in Q4) you place the probes between the terminals of an open contact then you will measure voltage due to the difference in potential between both terminals of the open contact
I'm thinking that you put the probes of your meter across a contactor.......... feeding a motor (single phase) on the live wire.

As the neutral also (normally) goes through the contactor, then the motor is isolated from the circuit when in the 'off' condition.

If I can measure a voltage by putting both probes across a contactor on the hot wire in the off condition I determine something is amiss.......

[oogene]

if you measure across nuetral to the "hot" side ; there is a potential difference and voltage will be measured; if you measure across open contacts something similar applies, there is a potenteial difference as one side of the open contact is at a lower potential than the other and if they are closed; they are at the same potential unless there is significant resistance in the "circuit" between ghe probes (or contact I.E.-burnt contacts)the vlotage meter has hgih resistance and it measures calulates it's voltage drop this assumes there is voltage resent in the circuit hope I got it right or at least close

[mekaniko5]

Hi moondawn.
Emerson climate technologies offer free online HVAC courses. The topic offerings are fairly extensive and totally free.
www.emersonclimate.com/onlineu (http://www.emersonclimate.com/onlineu)

[moondawn]

hi there mekaniko5

thanks for your post i will register with them and have a look
sounds too good to be true Free online courses!

thank you

Lee

[mekaniko5]

Have you tried registering?

[moondawn]

hi there i have had a lot going on and aint really had the time.

worked away for a while, am back now so will investigate it before i work away again

cheers

[Nadeem146]

are you awarded certificates if you take the exams on that website?