Simrad SC90, Руководство по установке

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The gate valve is manufactured by LK Valves. For more detailed information about
the gate valve and the Gate Valve Control Unit, refer to the technical documentation
provided by the manufacturer.
How it works
When the gate valve is open, the limit switch "NC" on the is also open. Once the gate
valve leaves the "open position" (starts to close) the "NC" limit switch is also closed.
This makes optocoupler U7 close too, sending "Inhibit" to the CPU on the Hoist Control
circuit board. The transducer can then not be lowered.
U2 is "closed" when the transducer is fully retracted. The ground level from pin 19 in
the Gate Valve Control Unit is then passed to pin 3, and the relay between pins 2 and 3
(in the Gate Valve Control Unit) is then activated. Pin 6 is +24 VDC. When activated,
this relay allows the gate valve to close. U2 is "open" when the transducer is not fully
retracted up, this is anywhere between fully lowered and "almost up". The relay between
pins 2 and 3 in the Gate Valve Control Unit is then deactivated. This prevents the gate
valve from closing.
If you loose power in the Motor Control Unit while the transducer is lowered, U2 will be
kept"open" due to the lack of power. This will cause the relay between pins 2 and 3 in
the Gate Valve Control Unit to deactivate. This prevents the gate valve from closing.
Minimum cable requirements
•
Conductors
: 4 x 0.75 mm²
•
Screen
: Overall braided
•
Voltage
: 60 V
•
Maximum outer diameter
: Defined by the cable gland
Related topics
Cable drawings and specifications, page 228
Cable layout and interconnections