LI-COR LI7200RS, Инструкция по эксплуатации

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Power Supply Fuse
The power supply is protected by a 5 A 125/250V, 5 × 20 mm fast-blow fuse (part
number 439-04214). If the battery or other power source fails to power the instru-
ment, check to see if the fuse has blown.
The fuse is located in the lower left-hand corner, as shown in Figure 5-5 on the pre-
vious page. Replacement fuses (part number 439-04214) are in the spares kit. Use a
flat blade screwdriver or your thumb to push down on the fuse holder cap and turn
counterclockwise to release the cap.
Accessory Fuse
The accessory uses a 2 A Nano
2
SMF Fuse. There is one spare fuse included in the
LI-7550. If the heated intake tube will not power on or continuously triggers an
error, check the fuse and replace it if necessary.
Replacing the Thermocouples
Important: Power off the gas analyzer (disable the power supply or disconnect
the power cable from the LI-7550) before conducting any maintenance that
involves disassembly or disconnecting cables. Disassembling the instrument or
detaching or attaching head cables while the instrument is powered on may dam-
age the instrument or result in a loss of data.
There are fine wire temperature thermocouples located in the air inlet and outlet
ports that measure the air temperature of incoming and outgoing air.
Do not insert
¼” Bev-a-line or other small diameter tubing into the air IN or air OUT fittings, as
you can break the fine-wire thermocouples present in each of the fittings.
If a ther-
mocouple does break, there are two replacement thermocouples in the spare parts
kit (part number 9972-007). Follow these steps to replace either air temperature
thermocouple:
1 Loosen the two knurled knobs on the top of the LI-7200/RS sensor head and remove the optical
path.
2 Use a 7/64” hex key (part number 610-03745) to remove the eight hex screws on the back of the
optical path.
Section 5. Maintenance
5-9 Power Supply Fuse