Thermo Scientific BF51634BC-1, Инструкция по установке и эксплуатации

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Introduction
Temperature Control System
Thermo Scientific 2-3
Temperature Control System
The 1700 °C Box Furnace temperature control system is located beneath the fur-
nace. The following is a brief description of the controls;
• Digital indicating controller, with a dual four-digit display screen.
BF51634BC,BF51664BC and C units use the programmable UP350 controller:
refer to Section “UT350 Controller Operation” . All other models use the
programmable appendix for detailed information.
• Thyristor with:
a. SCR Fuse
b. Current limit Potentiometer
• Amber lamp, located in the right front comer of the furnace, illuminates when
power is supplied to the unit and to the fans. The furnace is not necessarily
beating when this light is illuminated.
• Red lamp, located in the right front corner of the furnace, illuminates when
power is supplied to the heating element circuit. The furnace is not necessarily
heating when this light is illuminated.
• High limit over-temperature protection disconnects power to the elements. The
red lamp does not illuminate in this condition.
• Redundant over-temperature controller (option B) provides positive protection
for both furnace and the load ill the event of a control circuit failure. This option
includes an additional over-temperature controller and thermocouple. The red
lamp does not illuminate in the alarm condition.
• The Communication Option control system comes equipped with RS232 digital
communications which allows modification and interrogation of all instrument
control and configuration parameters from a remote computer. Refer to Figure
“Furnace Rear Access” for RS232 port location.
Heating Elements
The molybdenum disilicide heating elements are designed in a V-shaped
configuration to ensure long life, minimum distortion at extreme temperatures, and
easy replacement. These elements are resistant to thermal shock and can be
subjected to extremely rapid heat-cool cycling for prolonged periods of time with
no adverse effects.
The resistance of these elements does not change with use, which allows
replacement of individual elements at any time without matching the resistance
values of the new elements to the old elements. Refer to Section “ Heating
Element Replacement” for additional information.