Riken Keiki GD-F4A-A, Operating Manual

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10
４－８．Cautions at piping works
・ This unit is designed to sample the gas in an atmospheric pressure. Do not give an excessive pressure to
gas inlet and outlet of this unit.
・ Connect the exhaust pipe to the gas outlet located at the bottom of this unit and exhaust the sampled gas
to an area known to be non-hazardous.
WARNING
・
Use Φ8(O.D)-1t copper pipe and so on for piping.
・ Carry out piping works as straight as possible.
Excessively high load may cause burden on the suction pump, shortening the effective life of the pump.
When bends the pipe, secure R (radius of curvature) enough to avoid loading to the piping.
・ Determine the suction side piping length while considering the response time. When the gas is sampled
from the piping end (gas detection point), the response time of the gas detection sensor delay time
caused by the piping length becomes equivalent to the detector response time.
・ Be sure to attach the gas suction port at the end of gas detection point.
・ Be sure to put dust filter in front of gas detector. If sampled gas contains water and corrosive gases,
removal device is required separately.
・ Do not alter, noｒ remodel the parts, etc.
・ Use the circuit breaker as for the power of indicator/alarm unit. Also it shall be mounted nearby
indicator/alarm unit and be specified that it is for power interruption of indicator/alarm unit.
・ Ground the zener barrier separately corresponding to the A-class grounding with ground resistance of
10Ω or less.
・ Use the specified cable.
・ For system installation, operation and maintenance, take care not to damage the intrinsically safe
design.
・ The power of the indicator/alarm unit shall be turned on after completion of all wirings. If each wiring is
carried out in the power on condition, short-circuit between terminals or an electrical shock may be
occurred.
* NOTE
When wiring, read the operating instructions for the connected indicator/alarm unit.
WARNING
CAUTION
CAUTION