manufacturer :       Perkin Elmer

model :                   ATD 400

annotation :           Dokumente engl .

Model ATD 400 Specifications

The Model ATD 400 is a microprocessor-controlled, two-stage thermal desorption system. The analysis of up to 50 samples is performed automatically from the desorption of the sarnple tube to the final printed report.

The system utilizes a unique electrically-cooled, packed cold trap minimizing the risk of blockages by ice-plug Formation and allowing compatibility with samples containing significant amounts of water. The Model ATD 400 is compatible with any make of gas chromatograph and can be used with all GC column types ranging from ¼ inch packed to narrow-bore capillary.

Sample integrity is guaranteed by sealing the sample before and after desorption, and stringent leak test procedures are performed en each tube prior to analysis. The inert system flow path and the wide temperature range (-100 °C to +400 °C) give the Model ATD 400 an unmatched applications capability. Applications include atmospheric monitoring and the determination of volatiles in solids and Iiquids .

Stand-alone operation

The instrument is controlled through a keyboard and LCD display unit. Set and actual values of all parameters may be displayed at any time.

GC-controlled

When Iinked to Model 8600 or 8700 gas chromatographs configured with an automation board and Revision C or later versions of software, the ATD 400 can be controlled via the GC keyboard.

Gas chromatograph/ data system interfacing

BCD output of carousel position.

Contacts for ready and start, and full closed loop operation.

Sample tube capacity

50 industry-standard, patented * stainless steel sample tubes. Stainless steel tubes may be fitted with clips accepting adhesive labels for identification. (Removal is not necessary for analysis.) Glass and glass-lined tubes are also available. The sample tube carousel may be recycled repeatedly.

* British Patent No. 2064765; U.S. Patent No. 4350037 and equivalent foreign patents

Method storage

Four desorption methods can be stored in the instrument and "linked" together in sequence if required. (10 desorption methods may be used when the ATD 400 is controlled by a Model 8600 or 8700 gas chromatograph).

Desorption modes

Mode 1: Tube conditionirig    

Mode 2: Two-stage desorption

Mode 3: Discontinuous gas extraction

No. of desorptions per tube

Up to 99 (when set to 99, the tube is recycled until stopped by the user).

Primary Desorption Oven

Temp range

50 °C to 400 °C

Temp settings

1 degC increments over entire operating range.

Desorption time

1.0 min - 30.0 min. Settable in 0.1 min increments.

Cold Trap

Low temp range

-30 °C to +30 °C ( Peltier cooling) Standard

-100 °C to +30 °C (Liq.N ₂ cooling) Optional (Liquid Nitrogen Accessory, L427 0009 * ). Settable in 1 degC increments.

* British Patent applied for

High temp range

50 °C to 400 °C. Settable in 1 deg C increments.

Heating rates

Fast (40 degC /s)

Slow (5 degC /s) - for labile sarnple components.

Time held at high temp

0.0   to 30.0 min. Settable in 0.1 min increments.

Gas flow during trap heating

Forward flow or backflush flow.

Material

Quartz

NOTE: Gold trap heating may be activated independently to allow trap conditioning.

Calibration fadility

Optional gas sampling valve accessory for internal standard introduction. (Standard Injection Accessory, L427 0010.)

Transfer Line to Gas Chromatograph

Temp range

50 °C to 225 °C. Settable in 1 degC increments.

Material

Lined with 0.32 mm i.d . uncoated, deactivated fused silica tubing.

Heated Valve

Temp range

50 °C to 225 °C. Settable in 1 degC increments.

Sample Flow Paths

Temp

Maintained at heated valve temperature.

Material

Glass-lined stainless steel, PTFE or fused silica.

Carrier Gas Pressure Control

Pressure controlled supply. Settable from 0 to 30 PSIG (0 to 210 kPa ).

(Maximum inlet pressure 120 PSIG (830 kPa ))

Pneumatic Valve Actuation

Compressed air at 80 to 120 PSIG (550 to 830 kPa ). Intemal preset pressure control.

Maximum inlet pressure 120 PSIG (830 kPa ).

Sample Protection Sequence

Initial check for adequate carrier gas supply. Leak and pressure test completed on sample tube and cold trap before tube desorption. Ambient sample purge though the cold trap to remove air from sample tube prior to heating.

Sample Splitting

Split points available an the inlet and outlet of the cold trap allow independent control of the flow rates during primary desorption, secondary desorption and chromatographic analysis. This multiple splitting capability facilitates the selection of split ratios ranging from zero to

100 000:1.

Ambient Conditions

Temp range

15 °C to 32 °C

Humidity

75% relative humidity without condensation.

Power requirements

240 V ±10% 50/60 Hz 1.2 kVA

220 V ±10% 50/60 Hz 1.2 kVA

120 V ±10% 50/60 Hz 1.2 kVA

Weight

45.5 kg (100 lb)

Unit dimensions

Width               38 cm (15 inches)

Depth               60 cm (23.5 inches)

Height              50 cm (19.5 inches)