grounding conductor must be not less than 25mm
2
.
Fig 1
Appendix
Ⅱ
Clean Transparent Cover
In order to assure a clear image of dome, the under cover of dome should be cleaned
regularly.
l
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.
l
Please use a soft enough dry cloth or other alternatives to wipe internal and external
surface.
l
If dirt is serious, user can use a mild detergent. Any senior furniture cleaning
products can be used to clean the under cover.
Appendix
Ⅲ
Common Knowledge on RS-485 Bus
1. Basic Feature of RS-485bus
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).
2. Mode of Connection and Terminal Resistance
2.1 Industry standard of RS485 bus requires that connection in a 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.
