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When the tuning process is started the lower display will
flash “tunE” along with the furnace temperature set
point. During tuning the temperature set point cannot be
changed. To change temperature set point “tunE” must
be turned “OFF”.
High Alarm (Over Temperature Protection OTP):
Push scroll button until “AL.SP” (Alarm Set Point)
appears. The lower display should indicate 1010°C.
Depress either the “UP” or “DOWN” push button to se-
lect the OTP value you desire. Thermolyne recommends
that you set the value either at the maximum operating
temperature of the furnace or a value of 20 degrees
above your working temperature if you desire to provide
protection for your workload.
NOTE
If the power to the furnace is “turned off” or inter-
rupted while in “tuning,” upon return of power to
the furnace, the controller display will indicate
“LINE FAIL” because sampled data could be
questionable. To restart tuning, refer to “Tuning”
procedure.
If the controller cannot maintain temperature set
point “tunE FAIL” will appear on display. First, cor-
rect problem for not maintaining temperature set
point, then restart “tuning” procedure.
NOTE
HiAL- HIGH ALARM. (over-temperature protec-
tion, OTP)
The controller is fitted with a mechanical relay
which is de-energized in the alarm mode. This re-
lay, when de-energized, removes power from the
heating elements. If the primary control circuit fails,
the OTP will control the furnace temperature at the
preset value you have entered. It does not shut off
the furnace, but will maintain the chamber tem-
perature at that value.
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PERATION
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INGLE
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ET
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OINT
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ONTROL
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