What is FULL SPEED?

[truantjlj50]

Obviously, I am brand new to this, or I would not be asking this question.

When a firing schedule says:

900 degrees/hour to 1000 degrees; hold 1 minutes

FULL SPEED to 1500 degrees…. EXACTLY WHAT IS FULL SPEED?

There is nothing on my controller which indicates a choice of Full Speed.

Please forgive my ignorance.

 

[bookie13]

Warp 9

 

…….. I couldn’t help myself.

On most controllers it is a ramp speed of 9999.

Barry Kaiser

Web Site    http://www.kaiserglass.com

Glass Classes:   http://www.Kaiserglass.com/classes.html

Tutorials      http://www.kaiserglass.com/tutorials.html

[Vital-Spark]

In this electronic age that 9999 means AFAP (As Fast As Possible) whether going up or down seems archaic. I know there are limitations on the displays they use but I bet for a few bucks more most people would be happier with something more understandable. I understand that setting 9999 puts the kiln to the MAX ramp rate it can do, so why not say MAX Up/Dwn or even MAX with an arrow up or down. Fact is the engineers I have talked to at kiln makers outsource the controller design.

[Stephen Richard]

Every digital controller has a setting that is “full/always on” until the target temperature is reached on the way up.  On the way down the same setting means the kiln is entirely off until the target temperature is reached.   While fully off is the most frequent choice on the way down from process temperature to around the annealing point, it is not recommended on the way up.  Very fast tempeature rises confuse the controllers which normally require about half an hour to “learn” the temperature rise characteristics of each firing.  An afap up ramp will always overshoot the target temperature and sometimes by quite a lot.  More controlled firing is more desirable for more predictable results.

Stephen Richard

blogs at: http://www.verrier-glass.blogspot.com/   and  http://www.glasstips.blogspot.com/

[Vital-Spark]

All of this is correct but the point I was making (badly!) was this ‘on the way down’ phrase. The controllers switch of ok on the way down PROVIDED the target temperature is LOWER than the preceding temperature set. This vital point is never highlighted.

[Stephen Richard]

You are correct in saying that FULL can be full on or full off.  However it is only logical to understand that on the way up full is ON, and on the way down full is OFF.  If the existing temperature is lower than the target then the kiln power is on; if the existing temperature is higher than the target temperature, the kiln power is off.  There is no vital point to empahsise.  It is a contextual/conditional set of statements that reading of the manual elucidates.

Stephen Richard

blogs at: http://www.verrier-glass.blogspot.com/   and  http://www.glasstips.blogspot.com/

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