|
Detector Hardware for Retrofit on Thermo Trace, Agilent 6890, Varian, HP 5890, or SRI
GC Models - Compact detector towers made of
stainless steel and ceramic mount onto the existing FID or NPD base on the
GC, and use the GC's existing controls for setting detector temperature and
gas flows. Ion Sources identical to those used for the Agilent 6890/7890 NPD are on a self-aligning flange that fits the
tower top.
Electronics - A stand-alone DET Current Supply provides a precision
controlled constant heating current for the Ion Source for best response
stability versus time, plus a selection of Ion Source polarization for
optimum response in all modes. Thermo Trace NPD electronics provide
the most versatile control of heating current and polarization, while
Agilent, Varian, and SRI NPD electronics are more limited. The
Thermo Trace and Agilent 6890/7890 NPD Electrometers,
Varian TSD Electrometer, and SRI NPD Amplifier suffice for signal
measurement. Otherwise, a Keithley Model 6485 Picoammeter provides
a stand-alone unit for signal measurement for DET hardware mounted on HP5890
or the Agilent 6890/7890 FID detector base, as well as all DET stand-alone
Transducer equipment.
Compact GC Analyzer - DET tower hardware,
ceramic Ion Sources, and a Detector Current Supply are combined with a
compact SRI model 310 GC. Analyzer features a glass lined flash vaporization
injector, and a 15 m or 30 m x 0.32 mm fused silica column. Connection
to a laptop computer provides data analysis and time programming of column
temperature and carrier gas pressure.
Stand-alone Transducers and Detection Modules - TID/NPD
transducers are hardware assemblies fitted with Tube or Swage-type inlet
fittings for easy attachment to standard gas line connections. Detection
modules include these transducers in a thermally insulated box containing a
temperature controller and pneumatics controls where required. An RTIA
(Reactor Thermionic Ionization Analyzer) module includes a heated
reactor chamber as the inlet for the TID/NPD transducer.
Some
examples
of
DET equipment
uses:
 |
inexpensive, best
performance, highest quality ion source replacements for the Agilent 6890/7890 NPD - TID-2 (black ceramic for sharp P peaks) or TID-4 (white ceramic for best N-response), $350. each new or $315 each recycled. |
|
|
more stable Constant Current type ion source heating power
for the Agilent 6890/7890 NPD - substitute DET Current Supply ($1760) for the 6890/7890 Bead Voltage (Constant Voltage type) - other modes of thermionic detection also accessible with this equipment change. |
|
|
convert Agilent 6890/7890 NPD to selective detection of Oxygenates or volatile Halogenates - use DET Current Supply as above and replace NP ion source with TID-1 or TID-3 ($350. ea.). |
|
|
replace Varian TSD with DET NPD/TID
hardware for lower cost ion sources and much improved P-peak shapes - DET
NPD/TID/FID tower ($1650), TID-2 or TID-4 source ($350), and use compatible Varian TSD electronics.
Add a DET Current Supply for detection modes other than NPD. |
|
|
