User`s guide

Installation and Setup

the instruments cold trap. To install the dryer assembly use the

instructions provided with this assembly (Part No. N6710048).

Setting the Carrier Gas Flows

When you set the carrier flow you are setting the flow for the

desorption system which includes purging the sample tube, primary

and secondary desorption, inlet and outlet split flows and the GC

column flow rate.

Relatively high flow rates (20 to 100 mL/min) are required for

purging and desorption. Substantially lower flow rates (1 to 5 mL/

min) are required for capillary column chromatography. The

multiple splitter allows you to set the required desorption rates and

provides the lower column flow rates required by the GC. If your

application requires splitless operation you will need to install a

wide bore capillary column or a packed column in your GC in order

to handle the higher flows required for desorption.

You must set the Inlet Split flow manually using the Inlet Split

needle valve on the ATD/TD. You will set the Outlet Split flow

separately using the Outlet Split needle valve.

You must set the carrier pressure first. Then you will set the desorb

and inlet split flows. Lastly, you will adjust the outlet split flow rate.

You must power up the instrument before you can set the carrier

pressure and the various flow rates. Refer to Chapter 3 for

instructions on powering up and operating the ATD/TD.

Setting the GC Column Head Pressure

CAUTION

Do not power up the GC until you have established carrier

gas pressure and very dry air for at least 20 minutes. Dry Air

supply must be connected to the TD and air is flowing. The

cold trap and Peltier should be in an absolutely dry

environment before power is applied. Especially if a new unit

is just delivered or was off for a long period of time in a

humid area.