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Initial power-up – VICI D-3-I-7890 User Manual

Page 17

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13

Initial Power-Up

CAUTION: Always make sure that discharge gas is
flowing before heating and powering up the detector.

1. Before installing the column, set the gas flow to 30 ml/min (measured at

the detector vent). Let it flow for 15 minutes so that all air is purged from
the helium purifiers.

2. Plug in the helium purifiers and turn on the GC.

3. Set the detector temperature to 100°C and allow time for the detector and

helium purifiers to reach the set temperature.

4. Plug the 24 VDC output from the power supply (I-23569-1) into the pulser

module (PD-M2).

5. Plug the power supply cord to a 100 - 250 VAC source, and look through

the hole in the detector housing to see if the discharge is on.

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

6. Check the standing/background current, and record it in the Detector

Performance Log on the last page of this manual. Optimum range is
600 - 2000 pA at 100°C. Lower current indicates a clean, leak-free system.

7. The recommended detector temperature is 20°C above the column

temperature, with a minimum of 100°C. Set the detector to the operating
temperature required for the intended analysis. When the detector has
reached the set temperature, read and record the standing current.

8. Install the column as illustrated on page 11, leaving the oven at ambient

temperature. Start carrier flow, then read and record the standing current.

The difference between this reading and the one previous is the ionization
of the combined impurities in and eluting with the carrier gas. The smaller
the difference, the better the quality of the gas exiting the column.

9. Set the column oven to the temperature required for the intended

analysis. When the oven reaches the set temperature, read and record
the standing current.

The difference with the previous reading is the ionization of the column
bleed. The smaller the difference, the better the column is conditioned.

NOTE: Some stationary phases will have a higher bleed than others, but
are still suitable for this detector. However, the lower the bleed, the lower
the chances of contaminating the detector cell.

From this point, the standing current should be observed and logged after
any system change. In addition, logging the standing current (with and
without the column) on a regular basis is an effective monitor of system
integrity (leaktightness and cleanliness). We also recommend tracking the
internal standard (quantity on column/area count) for sensitivity continuity.

Installation

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