Susan Brown

[Susan Brown]

Yes, if you add another load in series, that changes the total resistance within that series circuit.

Which unit is this question in? I want to see it in context to make sure I answer correctly.

[Susan Brown]

The voltage in these equations is the voltage dropped across the load, not the source voltage. So, if a load was originally by itself in a circuit, dropping the source voltage, then another load is brought into series with it (by a switch activating), then the voltage drop across the original load will decrease. The current will also change.

[Susan Brown]

One example I thought of where this could happen is based on Question 8 on the Midterm Exam in the Core course where the Main Coil was shunted by the closed detector switch, leaving the Ignitor and Booster in independent, parallel circuits (*each* having 120v drop). When that switch opens, it becomes a series-parallel circuit, where all 3 loads will now share the 120v drop.

So any scenario where a load is either bypassed or brought back into series by a shunt will affect current and voltage to loads.

[Susan Brown]

“k” stands for “kilo”, which is 1000 of something. (For example, a kilometer is 1000 meters). So 5k-ohms is 5000 ohms.

See Mod. 4, unit 7, near the end of the unit for a table of units like this.

[Susan Brown]

Hi Ronald,
I have not heard of this. But I know we have a number of techs from TX at Appliantology – I suggest you post this in the Dojo and see what you can find out.

A lot of these types of licenses have more to do with knowing Code or other regulations, rather than actually understanding technology and troubleshooting, in which case the info you need is likely in that book.

Can you send me more info on this test? (A link?)

[Susan Brown]

The answer we are looking for is “It’s a PTC start device”. Essentially no one uses true relays anymore in this application, so it’s safe to just assume “PTC”.

[Susan Brown]

Those are correct. Good job!

[Susan Brown]

I just replied to your email, Jonathan.

[Susan Brown]

Always check the schematic. Some include a very clear chart of which color is what. Some you have to figure out by using your own savvy. They don’t all stick to the usual black/white convention, unfortunately. We’d have to see the diagram to know what the white wire you saw was.

[Susan Brown]

Hi Raja,
First of all, note that the question asks for the two most likely causes.

Of the three that you gave, the one that is not correct is “A broken agitator”

Here’s what we said in the lesson:

“If the motor is running, but the machine is not agitating, then you are most likely facing one of two issues, depending on the method your model uses to drive the agitator. On belt-drive models, a worn or broken drive belt causes this issue. Alternatively, on direct-drive models where the motor directly drives the transmission, the most likely cause is a broken drive coupler. This is a small plastic component that connects the drive motor to the transmission.”

The agitator is just that plastic center post with the fins. It is the items that cause it to move (belt or coupler) that usually are the cause of the issue.

Does that make sense?

[Susan Brown]

Tahj – are you getting the Midterm feedback emails I’ve been sending?

[Susan Brown]

Hi Tahj,
It’s easier if you start a new topic for each particular question. Or – if you just want to run a new answer by me, you can use email.

[Susan Brown]

See the email I just sent you.

[Susan Brown]

This question is designed to get you to think through the terminology. The fact that it is a “live circuit” means that voltage is applied, but does not necessarily indicate that current is flowing. An “NO” switch being “in its normal state” means that it is open. So, we are measuring across an open switch and would expect to measure the source voltage.

[Susan Brown]

Do you remember what we taught you about current in a series circuit?

It is the same at any point in the circuit. The electrons are all moving or none of them are moving. And if they are moving, they move at the same rate. This is where it is NOT helpful to think of water flow. Better to think of a tightly packed toy train track loop with no gaps between the train cars. If you push one they all move at the same rate.

So you can measure anywhere on the circuit, from wherever you can get the clamp around the wire.

[Author]

Posts