kfir katzin

[kfir katzin]

ok i sse,thanks for the detailed reply
so guess id want to figure out how many watts going into the motor(input) in the above mentioned case i just need to do IxE=P 13.2X115=1518w on the input and and there i have it!

[kfir katzin]

we first need to know what type of motor we are dealing with but in general we need OHMS of the coils,AMPS AND VOLTS and if we konw amps and volts we can easily calculate WATTS.AND IF WE KNOW WATTS AND VOLTS WE CAN READILY WORK OUT AMPS.
2.il give you and example,given on the nameplat are:
HP=1
VOLTS=115/230
FLA=13.2/6.6AMPS
EFF=70%
PF=70%
so i converted the HP TO WATTS 1HP=746W AND THEN DID P/E=I witch got me 746/115=6.48amps or if i do 746/230=3.243amp which i either case the amps dont coresspons to the specs on the nameplate and even if i try calculating the watts 115X13.2=1518w which is way out of the amps stated on the nameplate
why is it so?
this respectable looking guy explained in the vid that the correct formula is watts/volts x pfx eff
746/115 x0.70 x0.70=13.2
since we have losses of power and the rated power is the one coming out from the shaft rather than the power coming into the motor is he right about that?
https://www.youtube.com/watch?v=2cprO8ZdT1U&t=706s here is a link you can see for yourself at 8:45 minutes what im talking about.

[kfir katzin]

i know that every motor has an inductive reactance but you told me the i could use P=I*E AND its variations when i want to work out amps and watts of a non ohmic loads

[kfir katzin]

i need to have the techsheet as well as the schematic

[kfir katzin]

ok,thanks a lot

[kfir katzin]

OK GOT IT,THANK YOU FOR THE DETAILED REPLY

[kfir katzin]

hi
if i were to check the R door switchs would i do a continuity test across pin 1 and 3 or a voltage test across those pins is preferable? and if a voltage test is preferable what is the expected voltage reading across pins 1-3?
i guess 5vdc is the correct but since i dont want do rely on a guess im asking you.

[kfir katzin]

oh now it all makes sense to me,
thanks alot

[kfir katzin]

i can see how they get line and how they get neutral and i also assume that when the coils are energized they heat up the bimetal so it can open but i dont get why arent they old plain bimetals.
and why they need to have their own coils to heat them up intstead of openning in respons to the tempeture at the heater can or the blower housing.also i was wondering if they outwardly look the same as the regular bimetal
do you have a lesson which deals with those kind of bimetal so i can watch ?

• This reply was modified 1 year, 11 months ago by kfir katzin.

[kfir katzin]

i see, thank you alot
by the way, your lesson hasnt addressed the BIAS HEAT at all.
on the timer chart there are timer switches A-U AND Y-S entitled bias heat,they lead current to the 9 ohms coils beneath the outlet drum bimetal and the inlet control bimetal.
1.what does it mean by bias heat?and why does the dryer need it?
2.why would a bimetal have a coil? it seems weird
3.do these bimetal look the same as the regular ones? and how can i test them ?

[kfir katzin]

as iv learnt from you one of your lesson this thermal fuse there to to cut off power to the motor and stop it working in case the dryer has a grouded heating element ,so the user canot use the dryer until the dryer gets fixed ,id like to hear you take on this matter

• This reply was modified 1 year, 11 months ago by kfir katzin.

[kfir katzin]

its just a guess as learnt in lesson.is there any other explanation to this thermal fuse being in the motor circuit? id like to hear your take on this matter

[kfir katzin]

i think its a thermal fuse designed to go open cutting off power to the motor when there is a gronded heating element so the user can tell there is a problem and prevent the user using the dryer untill its fixed

[kfir katzin]

i think the one called out inlet control bimetal is hi-limit positioned on the heater can and the drum outlet is the operating tstat and its positioned on the blower housing.
and if the the control inlet bimetal openes and the drum outlet bimetal remains closed only the inner coil of the heater will stay on but the timer motor wont advance anyway.
the timer motor will advance only when the drum outlet bimetal opens.
on the other hand iv noticed another thermo hi limit to the left of the start switch is it a thermal fuse or a hi-limit bimetal? could a dryer have 2 hi limits? im a little confused

• This reply was modified 1 year, 11 months ago by kfir katzin.

[kfir katzin]

hi sam,
1.on your last video lesson at 1:40 the timer chart on auto dry coloumn there is a T-F (timer motor)timer contatct that is closed during auto dry you havent talked about and i also tried to find this on the schematic and didnt, how does this T-F CONTATCT come into play ?it definitly has something to do with the timer motor
2.why does the dryer need the control inlet bimetal to control the timer while it already has drum outlet bimetal which does both functions,shunts the timer stalling it and
put on the heating element whent heat needed? in other words the heating elenemt wont come on as long as the outlet drum bimetal is open,and when it cloeses the timer wont get any current and wont advavance anyway so why do we need the inlet control bimetalin the timer circuit?
its seems that the oulet drum bimetal does all the job of alternating between heating and switching the timer on and off,
3.besides why does the dryer need a another control bimetal for the outer heating coil heating element ? after all the drum outlet bimetal controls both coils and when it opens the whole heating element wont come on

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