Oxford Instruments Mercury iTC, Handbook

Page: 40 / 146

Handbook
November 2011 / 59-UMC0071 / Issue 01
Mercury iTC
Page 40
USER INTERFACE
Original Instructions

Gas Cfg
Tap once to access the Gas Flow Configuration page (see Section 3.2.10 ).

PID Table
Tap once to access the PID Table Editor page (see Section 3.2.11 ). This button is
only active if PID is set to Auto .
3.2.10 Gas Flow Configuration page
Figure 3-23 Gas Flow Configuration page
This page configures the gas-flow control loop, which is controlled by the optional
auxiliary I/O daughter-board. The page contains the following fields and controls:

Sensor
Select the sensor to be used for the gas-flow control from a drop-down menu.

TES
Enter the Temperature Error Sensitivity as a power of 2. e.g. enter 7 to set 512 (2
7
).
TES controls how fast the needle valve responds to a temperature error. Increasing
TES by 1 increases the response rate by a factor of 2.

TVES
Enter the Temperature Voltage Error Sensitivity as a power of 2. e.g. enter 6 to set
256 (2
6
). TVES controls how fast the needle valve responds to a heater-voltage error.
Increasing TVES by 1 increases the response rate by a factor of 2.

Min Gas Flow (%)
Enter a minimum valve position as a percentage of the maximum. Defining a
minimum valve position prevents the valve from closing fully, and possibly sticking.
Choose the minimum position so that there is no gas flow.

GFSF (%)
Displays the gas flow scaling factor.

HTT
Select a Heater Target Table file to use for the control.