Azbil Micro Flow MQV0002, Руководство пользователя

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CAUTION
The valve on this device cannot completely shut a flow off. If complete shutoff is required,
provide a shutoff valve separately. When the external valve is closed, it is necessary also to
fully close the valve of the device using either of the following methods:
•
Set the flow rate setpoint to zero.
•
Make the valve operation mode to fully closed.
If this valve remains in normal control status when the external shutoff valve is closed (zero
flow rate), there will be an excessively large flow as soon as the external shutoff valve is
opened. For the MQV0050(J, K), MQV0200(J, K), and MQV0500(J, K), if the external shutoff
valve is closed continuously for 5 minutes or more in control mode or with the valve forced
fully open, the valve overheating limit (AL71) will be activated and the current to the valve
will be forcibly limited.
Before connecting pipes with Swagelok or VCR connections, check the precautions in the
instruction provided by the connecting joint manufacturer.
When separately purchasing a connecting joint, use the following made by Swagelok Co.,
Ltd:
1/4” Swagelok: SS-400-1-6ST (standard)
SS-400-1-6STSC11 (oil-inhibited)
1/2” Swagelok: SS-810-1-8ST (standard)
SS-810-1-8STSC11 (oil-inhibited)
1/4” VCR: SS-4-VCR-1-00032SC11
1/2” VCR: SS-8-VCR-1-8STSC11 or equivalent
Observe the following when using the device (oil-free model) for oxygen gas:
•
Piping should be carried out by a specialist skilled in handling oxygen gas.
•
Use oil-free pipes and parts.
•
Be sure to remove foreign matter, burrs, etc. from the pipes before connecting the device.
The device is a precision instrument. Do not drop it or subject it to impact, or it might be
damaged.
When installing joints (UNF connections), secure the lower part of the main unit in a vise or
the like gripped between rags to protect the finished surfaces, and turn the joint to tighten.
Mount securely in order to prevent vibration. Otherwise, equipment failure could result.
Mount the device horizontally. Do not mount it with the display facing down. Doing so might
cause measurement error or equipment failure.
For the MQV0050(J, K)/0200(J, K)/0500(J, K). use the largest pipe possible in order to reduce
pressure loss in the pipes, and do not install any equipment near the MQV that can cause a
large pressure loss. If there is a large pressure loss in the pipes or equipment, the pressure
of the gas supply to this device (operation differential pressure) will be affected and will
fluctuate greatly with the flow rate. This could result in unstable control.
When making the pipe connections, hold the hexagonal part of the connector section and
turn the pipe to tighten. After connecting, check that there are no gas leaks.