42/24-10 EN Rev. 9
Chapter 9: Inspection and Maintenance
9-21
Limas11 UV: Lamp (EDL) Replacement
When should the
lamp be replaced?
Over a period of 2-3 years the plasma-discharge fill gas will dissipate, causing a
loss of lamp intensity. The lamp must be replaced when its intensity reaches a value
at which the short-term stability of the smallest measurement range is too low.
Status messages
When beam intensity becomes too low the appropriate status messages will be
displayed. For additional information see the “Status Messages” section,
page 10-13.
Determining Lamp
Service Life
Lamp service hours are displayed in the
Maintenance/Test
→
Analyzer
spec. adjustm.
→
Amplification Optimization
menu.
Step Action
Remove the old lamp:
1
Turn off the gas analyzer power supply.
Open the wall housing door or the 19-inch housing cover.
2
The lamp is hot (approx. 60 °C)!
3
Remove the cables to the light barrier boards
1
und
2
above the filter
wheels.
4
Remove the cables from the lamp
3
.
5
Loosen 2 fastening screws
4
of the support using a 3-mm Allen
wrench.
6
Remove the support with both filter wheels, step motors and lamp.
7
Loosen 2 fastening screws
5
of the lamp
3
using a 3-mm Allen
wrench.
8
Remove complete lamp
3
from the support
6
.
9
Loosen the 12-V-supply connector
10
.
Remove the fastening screw
8
with washer and holder of the tempera-
ture sensor
9
.
10
These parts are needed to mount the temperature sensor to the
new lamp!
11
Remove the temperature sensor
9
from the hole in the temperature
sensor block
7
.
12
Loosen 2 fastening screws
11
of the heater block and remove the
complete heater block from the lamp
3
.
Install the new lamp:
13
Before installing the new lamp, record the serial number shown on the
identification plate. It will be needed during amplification optimization.
Lamp Replacement
(see Figure 9-11)
14
Perform steps 3–12 in reverse order.
Continued on next page
