32
User Information
Introduction to Headspace and to the G1888 Network Headspace Sampler
Keypad and display
The Headspace Sampler has a 19–key elastomeric keypad with a
graphic LCD display. All functions of the sampler are controlled
from the keypad with the exception of EPC, which is controlled
from the GC or ChemStation.
Pneumatics
The Headspace Sampler uses two flow paths: Carrier gas flow
and flow for vial pressurization. There is a manual flow
controller for control of the GC carrier gas flow and a manual
pressure regulator for control of the vial pressurization. Use the
manual flow controller and manual pressure regulator when the
Headspace Sampler is set for manual pressure control (MPC).
When the Headspace Sampler is set for electronic pressure
control (EPC), the GC provides all flow and pressure control.
Toggle the flow mode between EPC and MPC using the switches
under the lid (
). Carrier gas and vial pressurization gas
do not have to be set to the same flow mode.
Four 1/8–inch Swagelok® bulkhead fittings are provided at the
rear of the pneumatic compartment for connecting vial pressure
and carrier gas lines. Two fittings are for MPC, and two fittings
are for EPC.
See
and
for diagrams of the pneumatics
system. The system is split into two drawings for clarity.
Figure 3
EPC/MPC toggle switches
MPC
EPC
Carrier gas
Vial pressurization gas
medium_standard.book Page 32 Tuesday, February 17, 2004 10:14 AM
