Agilent Technologies 7890 Series User manual

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Quick Reference Guide
7890 GC Heated Zones Quick Reference Guide
7890 Thermal Aux Zones
There are three (3) “Thermal Aux Zones” that can be configured to any of the six (6) physical
Heater/Sensor Connectors on the GC –per the assignments in the table below:
Heater/Sensor Connector Assignments for the Thermal Aux Zones:
Logical Aux Heater
Thermal Aux1
Thermal Aux 2
Thermal Aux 3
Physical Heater
Connection
Aux 1
Back Inlet
Aux 2
Back Detector
Aux 1, Aux 2
Front Inlet, Front Detector
The physical Aux 1 and Aux 2 Heater/Sensor connectors are mounted on the valve bracket and
are the most likely zones that you would assign to the Thermal Aux Zones.
The Rules for using the Inlet or Detector Heater Sensor connections are as follows:
If you want to use an Inlet connection as a Thermal Aux Zone, you must not have a
standard Agilent Inlet EPC module installed in the same position.
If you want to use a Detector Connection, you cannot have an associated EPC module or
Detector Logic board installed
7890 heaters must be between 10 and 180 watts. There is no configurable total power limit.
If total power/F or B channel > 220 watts, power priority to zones is 1-Inlet, 2-Aux, 3-Det.
Thermal Aux Zone Configuration Menus
NOTES: - Before turning on the GC, connect your heater/sensor to the zone to be used.
- Before making config. changes set the keypad Hard Configuration Lock to “OFF”
Access
Menu
Description
>
This shows 4 of the 26 configurable items
Direct Link to the
Thermal Aux Menus
NOTE: - You can configure a Valve
Box with Aux 1 or Aux 2 physical
heaters –or both!!!
As an example:
Select
“Thermal Aux 2”
Thermal Aux 2 is Unconfigured: It
can be configured as
A2 (physical heater/sensor Aux 2)
or B-DET (Back Det Heater/Sensor)
The actual heater power was
determined during the
”Power On Self Test”
Select
You can install A2 or B-DET for a
list of all configuration possibilities...
OR
Directly as a
MSD Transfer Line Heater

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Thermal Aux Zone Configuration Menus …continued
Access
Menu
Description
As an example:
Select
“Install Heater A2 ”
GC requests a Power Cycle –
This is not necessary yet –
Select
Move the cursor to
”Auxiliary type ”
Select
You will see four (4)
lines at a time!!
This is the current list of
All Auxiliary Type Heaters.
This list could grow in future
firmware releases as Agilent
implements more Detectors or
Accessories.
For the final example we will
configure a
”User Configurable Heater”
Move the cursor to
”User Configurable HTR”
select
Again you will see:
Again Select
From here you can input
custom configuration values for
your
”User Configuraeable Heater”
When all settings have been
entered you can finally
Power Cycle the GC
to make your changes take
effect!!!
Configuring a Flame Photometric Heater Configuration
Access
Menu
Description
Front or Back
Detctor
The FPD can be installed using only the
Detector heated zone with a Single
Sensor and Two Heaters connected in
parallel to the detector/xfer line.
OR:
By using the standard Two (2) heater
Configuration where the
Front FPD uses Aux 1 for the Xfer line
and the Back FPD uses Aux 2

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Procedure: Testing Resistance of the Heated Zone Heaters and PRT’s
WARNING: Before proceeding, turn off the main power switch and unplug
the power cord.
Caution: Make sure you are properly grounded with an ESD strap before
continuing.
Remove the GC panels required for access to the zone heater/sensor connector to be tested.
Remove the connector for the heated zone sensor to be tested –use an ohm meter to
measure the resistance of the PRT in question.
For heated zones the PRT is connected to the white wires on pins 2 and 3 of the connector.
The resistance of the PRT should correspond to those in the “Table of PRT Values”
The heater resistance can also be measured between the red wires on pins 1 and 4 –typically
23 Ω for a 70 watt heater (see table following).
With the connector removed from the GC, there should also be no connection to ground on
any of the four pins –this would indicate a possible shorted sensor or heater.
Table: PRT Resistance Values:
Pin 4 –Heater Ground
Pin 3 –Sensor Ground
Pin 2 –Temp Sense
Pin 1 –Heater Control

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6890 and 7890 Heater-Sensor Assemblies
Heated
Zone
Heater/Sensor
Assembly
Description
Heater Resistance
SS
G1530-67950
70 Watt Heater/
100PRT
23 
PP
G1543-61540
70 Watt Heater/
100PRT
23 
COC
G1545-60520
60 Watt Heater/
100PRT
26-27 
MMI
7890 Only
G3510-64100
(Whole Inlet Assembly)
160 Watt Heater/
Type K Thermocouple
Resistance cold 13 
9 
PTV
6890/7890
G2617-60506
(Whole Inlet Assembly)
150 Watt Heater/
Type K Thermocouple
Resistance cold 13 
9 
VI
G2319-60503
60 Watt Heater
100PRT
26-27 
FID
G1530-67950
70 Watt Heater/
100PRT
23 
TCD
G1530-67950
70 Watt Heater/
100PRT
23 
NPD
G1530-67950
70 Watt Heater/
100PRT
23 
uECD
G1533-60625
70 Watt Heater/
100PRT
23 
FPD
G1535-60610 –Block
G1535-60620 –Xfer Line
60 Watt Heaters
100PRTs
26-27 
FPD+
G3435-60610 –Block
G1535-60610 –Xfer Line
60 Watt Heaters
100PRTs
26-27 