| 摘要 |
PURPOSE:To transmit display information to a remote display device without the generation of a fire due to a spark or the like by setting up an optical information originating part in an explosion-proof box. CONSTITUTION:Oil from a tank truck or the like is supplied to an oil tank through a loading arm 1, a control valve 23 and a flowmeter 24. A valve controlling device and an optical signal transmitter are provided in the explosion- proof box 40 and connected to electric signal lines 82, 83, the valve 23 and the flowmeter 24 to control the valve 23 and fetch the flow rate information. The optical signal transmitter converts the flow rate information to an optical signal and transmits the optical signal from a transmitting part 70 to a receiving part of a display meter 32 attached to a canopy 31 e.g. in an oil station. |
