Signal Output

A standard signal channel, controlled via SIG 1 , always is provided.

A second signal channel, controlled via SIG 2 , is provided if Option 550/ Accessory 19242A (Communications Interface Board ), or Option 560/ Accessory 19254A (RS•232), is installed.

Output sources include detector signal(s), heated zone or oven temperatures, carrier gas flow rates, column compensation run data, or test chromatographic data. If both signal channels are present, each may output information simultaneously from the same source, or from two different sources.

For either channel, two separate levels of ANALOG output are provided, depending upon the analog signal cable used: +1 V or 1 mV.

0 to +1 mV:

for strip chart recorders.

-0.01 to +1 V:

for electronic integrators with analog inputs.

The two output levels are independent, and may be connected simultaneously to separate data•receivingdevices.

Note: A tick mark (electrical pulse) is produced at the +1 mV analog output when either START or STOP is pressed, and when a run times out (run time elapses). These marks locate beginning and ending points in a chromatogram plotted at a continuously running strip chart recorder.

Zeroing signal output

Acting on +1 mV and +1 V analog outputs, ZERO defines a constant offset which is then subtracted from the output signal (prior to signal attenuation by RANGE 2!( ) or ATTN 2!( ) ).

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