Scion Instruments 436-GC - Electronic Flow Control Type 21

Page: 132
436-GC/456-GC
730 Electronic Flow Control
SCION Instruments
436-GC/456-GC Service Manual Revision B February 2019
Electronic Flow Control Type 21
The EFC module used on an 1177 injector is the EFC21 or EFC25.
The EFC21 or EFC25 type is designed specifically for the split/splitless and PTV
injectors to support their various modes of operation. It duplicates the behavior of
the Split/Splitless manual pneumatics system in that there is an inlet mass flow
controller supplying carrier gas to the injector and a pressure control valve
downstream from the injector which sets the injector pressure. As injector
pressure determines the rate of carrier gas flow through the column, this pressure
is monitored close to the point of injection.
Type EFC21 allows the user to set constant injector pressure or constant flow. In
addition the split ratio can be programmed.
Optimized use:
 For capillary columns
 Flow & Pressure control
 Split injection use with split/splitless injector

Splitless injection use with split/splitless injector

Split injection use with PTV injector

Splitless injection use with PTV injector
EFC21
GC Control
Injector
Flow Control Unit
Septum
Purge
Digital Flow Control
Molsieve/Charcoal
CP742210 (silver color)
Carrier
Gas inlet
Septum
Purge Valve
CMOSens
®
flow sensor
Pencil
Filter*
Pressure Control Unit
P -Sensor
Charcoal
CP742211 (gold color)
Split Valve
Pencil
Split
Line
Filter*
Digital Pressure Control
Back Pressure
Controller
Split Vent
column