Miller Electric IH Welder User Manual


 
OM-203 185 Page 20
6-3-1. 2408 Controller
The 2408 controller in the IH/TS provides a means of establishing a heat profile for heating or stress relieving as
dictated by “code” requirements, and controls the power source to meet the programmed profile. The 2408 controller
has several screens (main and sub-menu) that are used to monitor status and program the control. The main
screens are as follows:
Home Screen: This screen is displayed after first turning on the unit. It has the actual temperature at the top of
the display and program temperature at the bottom of the display. Home Screen sub-menu and
definitions are shown in Table 6-1. Pressing the “Scroll”
button will step through the
sub-menus.
Run List: This screen is accessed by pushing the “Page” key twice. Run List allows the operator to
check the status of a program while the system is running. It also allows making changes to a
program by pressing the “Hold” button on the front of the IH/TS. Run List sub-menu
screens and their definitions are shown in Table 6-2.
Program List: This screen is accessed by pushing the “Page” key three times. Program List is used to
program the controller for a pre-heat or stress relieving temperature profile. Definitions of the
various terms found in the sub-menu screens are shown in Table 6-3. Typical programming
examples are shown in Figure 6-1, Figure 6-2 and Figure 6-3.
Access List: This screen is used to access the configuration and set-up sub-screens within the controller. This
area is password protected and should only be used by an experienced operator.
. Making changes in the Access List screens may cause the system to operate incorrectly.
A series of keys at the bottom of the 2408 controller are used to navigate between and change values in the various
screens on the controller display. Definition of the keys are as follows:
The “Page” key advances the controller display between main screens (Run List, Prog List and Accs List).
The “Scroll” key advances between various sub-menu screens in the main menus.
The “Up”
Y
and “Down”
B
keys are used to change values in the sub-menu screens.
. The two small round buttons on the front of the controller are disabled and nonfunctional.
6-3-1-1. 2408 Controller Operation
The 2408 controller is configured to control the power source to achieve the temperature program that is entered in
“Prog List”. The configuration of the controller contains two important elements that dictate how the controller
switches between segments and how it protects against over-temperature conditions.
One element is called “Holdback”. This is a temperature window that the controller uses to determine the point at
which it switches from segment-to-segment. The window is set to ±10°. When operating within a temperature pro-
file, the controller will not advance to the next segment until the actual temperature comes within 10° of the target
temperature.
The second element is an alarm. This alarm value is set at 25° F. When the actual temperature exceeds the target
temperature by 25° F, the controller shuts off the power source contactor to prevent overheating the part. When the
temperature falls 2° F below the alarm temperature, the controller re-energizes the power source output.