VICI D-4-I-SH17-R User Manual

Valco Instruments Co. Inc.

Pulsed Discharge
Detector
Model D-4-I-SH17-R
Instruction Manual

North America, South America, and Australia/Oceania contact:

Valco Instruments Co. Inc.

800 · 367· 8424 sales
713 · 688· 9345 tech
713 · 688· 8106 fax
[e-mail]

D4_shim_17.P65

Rev. 5/12

Europe, Asia, and Africa contact::

VICI AG International

Schenkon, Switzerland
Int + 41 · 41 · 925· 6200 phone
Int + 41 · 41 · 925· 6201 fax
[e-mail]

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Table of Contents

Introduction

Description and Operating Principles ..............................................................1

Safety Notes and Information ..........................................................................2

Symbols
Installation Category
Safety

Components of the Detector System .............................................................. 3

System Requirements

Components not Included with the Detector System ...................................... 4

System Purity ..................................................................................................4

Gas Specifi cations ..........................................................................................5

Installation

General Precautions .......................................................................................6

Mounting the Detector on the GC ...................................................................6

Gas Connections.............................................................................................8

Installing and Purging the Gas Regulator ...............................................8

Installing and Purging the Helium Purifi er ...............................................9

Connecting the Discharge Gas to the Detector .......................................9

Capillary Column Connection .......................................................................10

Packed Column Connection ..........................................................................10

Testing for Leaks ........................................................................................... 11

Pulser Module Installation .............................................................................12

Detector Electrical Connections ....................................................................14

Initial Power-Up .............................................................................................15

Mode Selection and Setup

Helium Ionization Mode.................................................................................16

Selective Photoionization Mode ....................................................................16

Troubleshooting ...................................................................................................18

Warranty ..............................................................................................................20

Detector Performance Log ...................................................................................21

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Introduction

Description and Operating Principle

1

The PD-D-4-I-SH17-R is a non-radioactive pulsed discharge ionization detector
(PDID) which is optimized for the Shimadzu GC -17, GC-2010, and GC-2014.
A schematic representation of the basic D4 detector is shown in Figure 1.

The D4 utilizes a stable, low power, pulsed DC discharge in helium as the
ionization source. Elutants from the column, flowing counter to the flow of
helium from the discharge zone, are ionized by photons from the helium
discharge above. Resulting electrons are focused toward the collector
electrode by the bias electrode.

The principal mode of ionization is photoionization by radiation arising from
the transition of diatomic helium

He

1

+

(

∑

)

A

u

2

to the dissociative 2He(1S

1

)
ground state. This is the well-known Hopfield emission. The photon energy
from the He2 continuum is in the range of 13.5 eV to 17.7 eV.

The D4 is essentially non-destructive (0.01 - 0.1% ionization) and highly
sensitive. The response to organic compounds is linear over five orders
of magnitude with minimum detectable quantities (MDQs) in the low
picogram range. The response to fixed gases is positive (the standing
current increases), with MDQs in the low ppb range.

Detector response is universal except for neon, which has an ionization
potential of 21.56 eV. Since this potential is close to the energy of the
He* metastable (19.8 eV) but greater than the photon energy from the
He2 continuum, neon exhibits a low ionization efficiency and low detector
response.

When a dopant is added to the discharge gas, the D4 also functions
as a selective photoionization detector. (Suitable dopants include Ar for
organic compounds, Kr for unsaturated compounds, or Xe for polynuclear
aromatics.)

GROUND PIN

DISCHARGE REGION

HELIUM INLET

HIGH VOLTAGE

SAPPHIRE INSULATORS

BIAS ELECTRODE

CAPILLARY COLUMN

VENT

COLUMN INLET

Figure 1: Schematic of the D4 detector

COLLECTOR ELECTRODE

Introduction

2

Helium Ionization (PDHID)

The PDHID is essentially non-destructive (0.01 - 0.1% ionization) and highly
sensitive. The response to organic compounds is linear over five orders of
magnitude with minimum detectable quantities (MDQs) in the low or sub
picogram range. The response to fixed gases is positive (the standing
current increases), with MDQs in the low ppb range.

The PDHID response is universal except for neon, which has an ionization
potential of 21.56 eV. Since this potential is close to the energy of the He*
metastable (19.8 eV) but greater than the photon energy from the He
continuum, neon exhibits a low ionization efficiency and low detector
response.

2

Photoionization (PDPID)

Changing the discharge gas from pure helium to helium doped with argon,
krypton, or xenon changes the discharge emission profile, resulting in
resonance atomic and diatomic emissions of the rare gas added. Response
is limited to sample compounds with ionization potentials less than or equal
to the dopant gas emission energy. In this configuration, the detector is
essentially functioning as a specific photoionization detector for selective
determination of aliphatics, aromatics, and amines, as well as other species.
Since there is no lamp or window, sensitivity will not change with time.

Safety Notes and Information

CAUTION: During normal operation, the detector pro­duces ultraviolet energy (UVA, UVB), some of which may
be emitted. Do not watch the arc without eye protection.

Symbols

HIGH VOLTAGE

Voltages presenting the risk of electric shock are present in
several places in the equipment. Avoid contact with hazard­ous live parts. Do not probe into openings or attempt to
defeat safety mechanisms.

HOT SURFACE

The surface of the detector body may be hot while in opera­tion (possibly in excess of 250°C). Caution should be
observed.

ATTENTION

Refer to the manual.

Introduction

Components of the Detector System

Detector system components are listed in Table 1. Check the contents of the packages to
verify that everything is present. Contact the factory if anything is missing or damaged.
(NOTE: damaged shipments must remain with the original packaging for freight company
inspection.) Tabl e 2 lists additional items which must be purchased from Shimadzu.

3

Table 1:

Components of the D-4-I-SH17-R system

Description Quantity Product number

Detector cell, PDHID 1 PD-D4-I-RU

Pulse supply module 1 PD-M2

Instruction manual 1 MAN-PDD4-SH17

Fittings kit 1 PD-KIT-D4

Includes: 1/32" polyimide ferrule 5 ZF.5V

1/32" polyimide plug ferrule (no through hole) 1 ZF.5VX

1/16" gold-plated ferrule 5 ZF1GP

0.25 - 0.44 mm polyimide column ferrule 5 FS.4

0.4 - 0.5 mm polyimide column ferrule 5 FS.5

1/16" union, 316 SS 2 ZU1MS6

1/16" tee 1 ZT1

1/8" external to 1/16" internal adapter 2 EZR21

1/8" external to 1/16" internal reducing union 2 EZRU21

1/32" external nut 1 EN.5KN

Fused silica adapter (installed) 1 IZERA1.5

Packed column adapter 1 I-23642-D4RU

Restrictor, 30 cc/min @ 60 psi He 1 TGA-R-30F60P

Helium purifier 1 HP2

Electrometer cable assembly, Shimadzu 1 I-23230-SH

Bias cable assembly, Shimadzu 1 I-23404-SH

Pulser power supply 1 I-23569-1

Heater block assembly, Shimadzu 1 I-23831A

Table 2:

Components not supplied by Valco (may be obtained from Shimadzu)

Description Quantity Product number

For GC-17

Mounting base screws 2

Heater assembly (depending on requirement) 1

120V 221-43346-91

220V 221-43346-93

Electrometer, FID wide range (see page 12) 1 221-43290-91

For GC-2010

10 mm spacers, BSU-410 2 037-38871-72

FID-2010 heater assembly, 220-240V 1 221-47660-98

FID-2010 controller 1 221-46520-91

For GC-2014

10 mm spacers, BSU-410 2 037-38871-72

FID-2014 heater assembly, 220-240V 1 221-70610-34

FID-2014 controller 1 221-46520-92

Introduction

4

System Requirements

Components Not Included with the Detector System

• Helium (99.999% purity) and other support gases

• Ultra high purity grade gas pressure regulator with stainless steel

diaphragm

• Any special adapters required for connection to the gas regulator

• SS tubing to go from gas supply to GC

• Flow measuring device

System Purity

Discharge/Carrier Gas Considerations

The performance of the detector is adversely affected by the presence
of any impurities in the gas streams (carrier, discharge, or dopant). We
recommend that a quality grade of helium 5.0 (99.999% pure or better)
be used at all times. Major gas suppliers offer research grade helium
(99.9999% pure) which is particularly low in fixed gas impurities and should
give good results in a clean system, but even the highest quality carrier
gas may contain some water vapor and fixed gas impurities; hence a
helium purifier is included as part of the detector system.

must always flow through the helium purifier.

The discharge gas

Whenever a new batch of discharge gas is received, we recommend
performing a blank GC analysis of the gas in the PDHID mode to detect
and identify the presence of any impurities. Gas purity requirements
are specified on the next page.

Tubing

Standards of cleanliness that are suitable for many GC applications may
be totally inadequate for the sensitive PDHID/PDPID work. All surfaces that
contact the gas stream must be fused silica or stainless steel. Do not use
copper tubing or brass fittings. All tubes must be thoroughly cleaned and
baked before use.

Flow Controllers

The use of valves or flow controllers in which the gas stream is exposed
to any polymer-based packing or lubricating material is to be particularly
avoided.

Pressure Regulators

We recommend commercial “ultra-pure” grade regulators with stainless steel
diaphragms. Regulators with diaphragms made of neoprene or other
elastomers should never be used.