YOKOGAWA EXAxt ZR402G, User Manual

Page: 138 / 169

<10. Other Functions>
10-21
IM 11M12A01-04E 11th Edition : Jul. 19, 2017-00
10.5 Handling of the ZO21S Standard Gas Unit
The following describe how to flow zero and span gases using the ZO21S Standard Gas
Unit. Operate the ZO21S Standard Gas Unit, for calibrating a system classified as System 1,
according to the procedures that follow.
10.5.1 Standard Gas Unit Component Identification
Applies the power to operate the
pump to supply the span gas.
Carrying case
Flow checker
Span gas valve
Checks the zero and
span gas flow.
Controls the span gas (air) flow.
Zero gas valve regulator
Tube connection
Cover screws (six pcs.)
Pump
Supplies span gas (air)
Gas cylinder
Contains the zero gas. A gas
of 7 Nl is charged to 700 kPa
Clamp
Clamps the gas cylinder.
Zero gas valve
Attaches to the gas
cylinder for use.
Power cord
F10.14E.ai
Figure 10.4 Standard Gas Unit Component Identification
10.5.2 Installing Gas Cylinders
Each ZO21S Standard Gas Unit comes with six zero gas cylinders including a spare. Each
gas cylinder contains 7-liters of gas with a 0.95 to 1.0 vol% O
2
(concentration varies with each
cylinder) and nitrogen, at a pressure of 700 kPaG (at 35°C).
The operating details and handling precautions are also printed on the product. Please read them
beforehand.