Thermo Scientific Mercury Freedom 80i, Manual

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Introduction
Model 81i
Thermo Fisher Scientific Mercury System Manual 1-3
(Model 82 i ), and a Hg probe (Model 83 i ), along with additional peripheral
components, such as a zero air supply, umbilical, and instrument rack.
However, the Model 81
i is also available as a stand-alone calibrator.
Table 1–1 shows the Model 81 i solenoid valve status for the different
calibrator modes. Use this table along with Figure 1–2 when reading the
principle of operation description that follows. Note that a valve status
shown as ON describes a valve that is energized, or in the Normally Closed
(NC) state. A valve status shown as OFF describes a valve that is de-
energized, or in the Normally Open (NO) state.
Table 1–1. Model 81
i
Valve Mode Status
Solenoid ID Standby Instrument
Zero Instrument
Cal Orifice
Zero Orifice
Cal System
Zero System
Cal
Valve 1 ON ON ON ON ON ON ON
Valve 2 OFF OFF ON OFF ON OFF ON
Valve 3 OFF OFF ON OFF ON OFF ON
Valve 4 OFF OFF OFF ON OFF ON OFF
Valve 5 OFF OFF ON ON OFF ON OFF
Orifice Valve OFF OFF OFF ON ON OFF OFF
Spike Valve OFF OFF OFF OFF OFF ON ON
Clean, dry, Hg-free pressurized air/nitrogen (30-40 psig) feeds both a high
flow (0-20 slpm) dilution air mass flow controller (MFC) and a low flow
(0-50 sccm) Hg source MFC (
Figure 1–2
).