Kayden CLASSIC 810, Руководство по эксплуатации продукта

Страница: 13 / 72

5
Shop Online
CLASSIC 800 Product Manual
Introduction
III. THERMAL SIGNAL
The CLASSIC 800 senses changes to the temperature differential as changes occur in the process. The “value”
being sensed and displayed as the Thermal Signal is the rate of thermal dispersion. Assuming the added energy
from the heater is a constant, the formula that determines the Thermal Signal has only two variables:
1) The thermal conductivity of the process media, and
2) The velocity of the process media past the sensor.
The relationship between Thermal Signal and velocity is non-linear. When one of these variables is constant in
a given application, the value of the other variable can be monitored by the CLASSIC. The Thermal Signal Bar
Graph displays Flow & Level as a percentage of the switch/transmitter’s full scale capability.
Figure 2 below illustrates the
Thermal Signal LED indicators moving to the right as process velocity increases.
Assuming a constant heater power and a consistent process media, as the velocity of the process increases so
does the Thermal Signal , represented by movement of the illuminated LED to the right.
For example, if the left-most LED is illuminated on the Thermal Signal Bar Graph , then a minimum amount of
heat is being carried away by the process based on the current settings. If the right-most LED is illuminated on
the Thermal Signal Bar Graph this indicates the maximum amount of heat is being carried away by the process
based on the current settings.
No Flow or Dry (Level)
Increasing Flow
Maximum Flow or Wet (Level)
Thermal Signal 100% 0
Relay 1
Relay 2
Fault
Set Point 1
Set Point 2 Run Mode
Bypass
RUN
SET
1 2
CLASSIC
™
Thermal Signal 100% 0
Relay 1
Relay 2
Fault
Set Point 1
Set Point 2 Run Mode
Bypass
RUN
SET
1 2
CLASSIC ™
Thermal Signal 100% 0
Relay 1
Relay 2
Fault
Set Point 1
Set Point 2 Run Mode
Bypass
RUN
SET
1 2
CLASSIC ™
- No flow or flow is minimal
- Flow is increasing
- Flow is at maximum velocity
- Level of process is below
sensor
- Level of process is above
sensor
Figure 2 - How Thermal Conductivity is Displayed