Bird Technologies 6091P - Manuale (Pagina 29)

Typical response times for the Calorimeter are shown in figure 11. The first curve
shows the response time with power stepped up from 0 to 200 watts. The second
curve indicates the response when the input is stepped down from 200 to 0 watts.
The step-down response time is considerably longer than the step-up response time.
This is due to residual heat stored in the system.
Measuring Coolant
Flow Rate
The flow rate is displayed in liters per minute. The flow rate should be between 0.284
to 0.473 liters per minute. An alarm will sound if the flow rate drifts outside of this
range.
1. Press and hold the FLOW pushbutton to check the coolant flow rate.
2. Release the FLOW pushbutton to return the display to the power dis-
play mode.
Measuring
Temperature
Differential (
DT)
The temperature differential is displayed in degrees Celsius. The ∆ T is normally be-
tween 0.380° to 7.610°C and increases linearly with the RF power input level. An
alarm will sound if the ∆ T exceeds 8.500°C. If the alarm sounds, shut down according
to the emergency shutdown procedures in this chapter.
1. Press the ∆ T pushbutton to check the rise in temperature as the cool-
ant passes through the load resistor.
2. Release the ∆ T pushbutton to return the display to the power display
mode.
GPIB Operation
The Calorimeter is capable of remote operation via the General Purpose Interface
Bus (GPIB). Detailed information relating to bus capabilities together with program-
ming examples are detailed in Appendix A - Remote Operating Procedures.
Normal Shutdown Procedure
When power measurements are completed, shutdown the Calorimeter as follows:
CAUTION
Never turn off the Calorimeter’s main power switch while RF source power is applied to
Calorimeter input. Failure to turn off RF power source can result in major equipment
damage.
1. Turn off RF power source device.
17
Operating Instructions
Figure 11
Typical
Response Times