Alternating Station Circuit

  • Hi Guest

    We will be moving G Scale Central to a new server at 7pm GMT on Monday 30th January, if you see this message after that time then you are still on the old server so do not post anything as it will not be transferred to the new one. Once this message is no longer visible to you, then you are on the new server.

    There will be no site changes at all, just moving to a new server (faster, shinier, better etc etc)

    Paul

Greg Elmassian

Registered
8 Mar 2014
7,398
944
San Diego
Country
Armenia
www.elmassian.com
Best answers
0
Country flag
Yeah, but the current through a varistor generates heat, which matches the definition of thermistor, and of course Wikipedia is a poor source.

I have a number of electrical and electronic engineers working for me, some with PHD's, you always specify the temperature coefficient, or there are just certain other descriptions, everyone understands the temp coefficient and use of a MOV for example....

In any case without specifying PTC or NTC you are asking for confusion. There is also a small typo on the variable resistor, "device that can adjust it's resistance".... I surely hope not! When potentiometers start adjusting themselves, we are in trouble!


Greg
 

JimmyB

Now retired - trains and fishing
23 Feb 2018
5,609
762
68
Weston-super-Mare
www.tumble-down-falls.co.uk
Best answers
0
Country flag
Yeah, but the current through a varistor generates heat, which matches the definition of thermistor, and of course Wikipedia is a poor source.

I have a number of electrical and electronic engineers working for me, some with PHD's, you always specify the temperature coefficient, or there are just certain other descriptions, everyone understands the temp coefficient and use of a MOV for example....

In any case without specifying PTC or NTC you are asking for confusion. There is also a small typo on the variable resistor, "device that can adjust it's resistance".... I surely hope not! When potentiometers start adjusting themselves, we are in trouble!


Greg
Greg it would seem you are never wrong, just everybody else :)
 

Greg Elmassian

Registered
8 Mar 2014
7,398
944
San Diego
Country
Armenia
www.elmassian.com
Best answers
0
Country flag
No, it's just in my area of expertiese, our current designed board is 12 layers and 4,000 components. I am well versed in "parts description frustration".

The salient part, the Negative Temperature Coefficient, vs. Positive Temperature Coefficient makes a HUGE world of difference in using these components. Get the wrong one and your circuit works in reverse.

Your inrush limiter (in a keepalive situation) becomes a current blocker, for example

Merely copying stuff from Wikipedia is dangerous, as virtually anyone can post to Wikipedia.

You do not see me advising in scratch building, 16mm scale, weathering, live steam port timing do you?

Finally this is not a case of being wrong, just insufficient information to be successful.

Greg