OperatorManual.pdf - 第33页
As soon as a board passes S1, the following will happen: z Stand-by N2 will be shut off z Main N2 will be activated z N2 re-purge will be activated z The oven will go to a stabaliz e status SMEMA will not allow boards to…
N2 conservation (optional)
The N2 conservation mode allows you to set a timer to switch the main N2 supply off to the XPM oven after the
oven is empty of processing boards beyond the set timer period. During the conservation mode, the 'stand-by' N2
valve will be active. The user can set a regulator to control the 'stand-by' amount of N2.The main purpose of this
mode is to optimize N2 usage during extended idle periods.
The conservation mode has the following setings:
z Time out[min] - the time that the machine has to be empty before the conservation mode kicks in. If 0,
inactive.
z
Fans[rpm] - the fan speed in conservation mode. If 0, recipe fan speed
z Purge[min] - the N2 purge time when returning to normal mode
The settings mentioned above are located in the configuration under the atmophere tab.
Principle of operation
S1 :
upstream sensor
positioned outside the XPM oven. To optimize against restricting board travel in the
production line, sensor S1 should be placed far enough prior to the onload of the oven. This is to allow the XPM
oven sufficient time to switch from N2 conservation mode and to re-establish the O2 ppm level prior to a board
arriving at the oven, without stopping a board prior to the oven. The wait time of the boards in front of the oven
should be minimized to prevent blocking the line for an extended period.
S2 :
board entering sensor
positioned at the entrance of the XPM oven.
S3 :
board exiting sensor
positioned at the exit of the XPM oven.
If the XPM oven starts up with a N2 recipe, the main N2 valve and the purge valve are activated. The length of
purge time in minutes is controlled by the purge time setting in the recipe. As soon as the purge is finished and all
the parameters are stable, the oven will go into a
ready
status. At this point boards are allowed to enter the oven.
If the oven is empty and there are no boards between sensor S1 and the oven, the N2 conservation time-out timer
will start. When the time-out expires, the oven switches to N2 conservation mode. This means:
z The main N2 supply is shut off
z
The 'stand-by' N2 supply is activated
z A N2 conservation indication will appear on the PC screen
z
The yellow lamp on the light tower will light
z SMEMA will not allow boards to enter the XPM oven
Operator manual 32 August 2003
As soon as a board passes S1, the following will happen:
z Stand-by N2 will be shut off
z Main N2 will be activated
z N2 re-purge will be activated
z
The oven will go to a
stabalize
status
SMEMA will not allow boards to enter the oven until the oven is
Ready
The event that a board is between sensor S1 and the XPM oven is latched. This appears on the screen as '
N2
conservation inhibited
' . This latch is cleared after the oven is completely empty. This means that the N2
conservation time-out should be set longer then the time that it takes for a board to travel from sensor S1 to
sensor S2 in the oven.
Operator manual 33 August 2003
Start/stop timer
Go to the main menu and select
S
etup
,
A
u
to
Start/Stop There are 2 choices in the menu.
1.
Weekly Timer- The weekly timer is the typical timer function to use to schedule repeated weekly oven start
and stop events.
2.
Special Event Calandar- This timer function is used with the calendar to program one-time events, e.g. out
of the ordinary oven start/stop times.
The weekly timer
A separate start and stop time is displayed for each day of the week in the weekly timer. A new time can be typed
directly after clicking on a time edit box, or the
up/down buttons
can be clicked to increase or decrease the
current time setting. Each time entry is separated into hours and minutes items. All time settings are stored in the
Windows registry. A time entry of 00:00 is disregarded to allow a corresponding start or stop event to be skipped
on a given day or for several days if required.
For more details :How Does the Timer Work?
A
checkbox
below the start/stop times enables or disables the use of the timer function. The
icon button
with
the clock and the hand is a toggle switch between the start and stop status of the timer.
The
Clear button
changes all of the timer settings to zero (00:00).
The
Close button
closes the weekly timer.
IMPORTANT
The timer icon on top of the screen indicates that the timer function is in use.
IMPORTANT
The start/sto
p
timer uses the 24 Hour clock!.
10:15 AM is 10:15, however, 10:30 PM is 22:30
IMPORTANT
It is only possible to use the toggle switch if the timer function is enabled. The timer icon (clock)
on the icon bar on top of the main screen indicates the timer function is enabled. The icon is
green with a closed contact when the timer is active, and grey with an open contact when the
timer is in standb
y
mode.
Operator manual 34 August 2003