Videoswitch CMOR Vi-D5000 Dome - Manual (Page 35)

Vi-D5000 IR Dome
Videoswitch Page 30 VD601A.DOC
5.2 Clean Camera Window
In order to assure a clear image of dome, the under cover of dome should be cleaned regularly.
• Be careful when cleaning and hold the outer ring of under cover by hands to avoid directly touching
with it. Because the acid sweat of finger membrane may corrode the surface coating of under cover.
Hard tool scratching the under cover may lead to blurring the images of dome so that affecting image
quality.
• Please use a soft enough dry cloth or other alternatives to wipe internal and external surface.
• If dirt is serious, user can use a mild detergent. Furniture cleaning products can be used to clean the
cover.
5.3 RS485 Bus
5.3.1 Basic Feature of RS485bus
According to industry bus standard of RS-485, RS-485 bus is half-duplex communication bus with the
characteristic impedance of 120Ω, whose maximum load capacity is 32 payloads (including the master device
and the controlled device).
5.3.2 Mode of Connection and Terminal Resistance
Industry standard of RS485 bus requires that connection mode of daisy chain should be used between the
devices with 120Ω terminal resistances connected at the both ends.
As shown in fig. 26 and fig. 27 is simplified connection, but the distance of part "D" shall not beyond 7 meters.
Fig 26
Fig 27
120Ω terminal resistance is connected as shown in fig 27.
The 120Ω terminal resistance is available in the dome. When needing to connect 120Ω resistance, toggle the
8th bit of DIP switch SW2 to "ON" . This way the 120Ω resistance is connected to the circuit.