Thermo Scientific SOLA II, User Manual

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The X-Purge System
Maintenance
Thermo Fisher Scientific SOLA II User Guide G-7
If AC power or purge pressure is lost, the X-Purge unit shuts off power to the
analyzer system. When the power or purge pressure is restored, the X-Purge
begins the purge timer. After the required purge time is achieved, the X-Purge
unit applies power to the analyzer system.
The X-Purge controller interrupts the incoming analyzer electrical power.
Power to 4–20 mA outputs is interrupted upon loss of purge or power, as the
analyzer powers these outputs. The device receiving discrete and/or Modbus
signals from the analyzer may apply power. Consequently, the purged analyzer
enclosure could contain powered wiring even when power to the analyzer is
interrupted. To ensure that the purged analyzer enclosure contains only non-
incendiary power upon interruption of main analyzer power, you may elect to
implement one of the following:
λ
Install the appropriate Intrinsically Safe (IS) barriers on Modbus and/or
discrete signals.
λ
Utilize the X-Purge’s alarm contacts to drive interposing relays configured
such that the Modbus and/or discrete signal wiring continuity is broken
upon loss of main analyzer power.
Caution
Placing the NORMAL / BYPASS switch in the BYPASS position
disables safe operation of the system. The BYPASS position is to be used
ONLY when required for maintenance AND only if the area is non-
hazardous.
σ
Caution
Do not open the explosion proof housing for the X-Purge unless the
area is known to be non-hazardous.
σ
Caution
Do not leave the NORMAL / BYPASS switch in the BYPASS position
after maintenance is completed. Do not leave the analyzer system unattended
when the NORMAL / BYPASS switch is in the BYPASS position. Personnel
must remove power from the system immediately if hazardous conditions are
suspected.
σ
Power or Purge Loss
Shutdown
Maintenance