Teledyne 3300TB, Руководство по эксплуатации, Страница: 41 / 51

Maintenance Model 3300TB
Teledyne Analytical Instruments 28
3. Insert a small flat-blade screwdriver into the slot in the
receptacle wall nearest the fuse and gently pry open the fuse
receptacle. The fuse holder will slide out. There are two fuses
in use and are visible in the clip.
4. Remove the bad fuse and replace it with a 5x20mm 0.5 A,
250 VAC, IEC time lag (T) fuse (P/N F1128).
4. Replace the fuse holder into its receptacle, pushing in firmly
until it clicks.
5.2 Sensor Installation or Replacement
5.2.1 When to Replace a Sensor
On the trace analyzers, the Micro-fuel Cell will typically fail due to
excessive zero offset caused by loss of water. Large zero offsets will
result in inaccurate SPAN settings. To test for this condition, purge the
sensor and sample system with ZERO gas (typically nitrogen with less
than 1 ppm O2). It may take several hours for the sample system and
cell to return to a stable low level of O2 if it has been exposed to higher
levels of O2. If the instrument will not come down to an acceptably low
reading on zero gas, then a depleted cell or a sample system leak should
be suspected. Typically offsets of 1.0 ppm or less are acceptable. A
Cell failure may also be indicated by an inability to SPAN, or slow
response to changes in O2 concentration at levels below 100 ppm.
CAUTION: Read the section Cell Warranty Conditions,
below, before replacing the cell.
CAUTION: After replacing the Micro-Fuel Cell, the analyzer
must be recalibrated. See Calibration in Chapter
4.