|
1. How to choose a reader?
1.1. Firstly, find out the type of card that your system is using, card of different type uses different card reader.
E.g. EM Card uses EM Reader; Mifare Card uses Mifare Reader, Census Long Range Card uses Census
Reader. Above mentioned are cards frequently used in today's market.
EM Card only provides Card ID, it is cheap and
suitable for door access, time check and card park usage,
not appropriate for payment. If the system incorporate payment,
it is advisable to use Mifare Card.
Mifare Card, very popular and recommendable
card. The biggest characteristic of this card is it is a
read and write card and able to store data to the card,
hence it can be used as an electronic purse to store value.
It is very much suitable to be use in one card solution.
The price is slightly higher than EM Card and reading distance
smaller than EM Card.
Census Card is a long range card, reading range
can goes up to 3m, suitable for use in human tracking, vehicle
tracking and car park management.
1.2. Be sure to choose using wiegand reader or RS-485 reader. The biggest difference is the communication
distance. Distance between controller and wiegand reader is only at 33m, whereas with RS-485 can goes
up to 1,200m. But communication speed will slow down when using RS-485 especially when the number of
mounted readers increases compare to wiegand reader. One more thing to take note is for RS-485 reader,
is a must to use shielded twisted pair cable to connect with controller. As for wiegand reader, normal
shielded cable will do.
1.3. In Smartkey System, SK200 2-Doors Controller can connect up to 4 wiegand readers and 4 RS-485
readers; SK400 3-Doors Controller can connect to 8 wiegand readers and 8 RS-485 readers; SK100 Single
Door Controller can only connect to 2 wiegand readers, therefore it can't connect any RS-485 reader.
1.4. Although same type of card is used but not all the time the reader used using the same connection
distance. Therefore, need to know the reader distance.
2. How to choose a controller?
2.1. When cost is taking into account, advise if is possible do consider to choose SK400 controller as it controls up to 4 doors. The more doors used, the more should consider 4 doors controller.
2.2. Single door controller has the most simplified wiring and convenient maintenance. But the cost of choosing 4 single door controllers could be higher than a 4 doors controller. Therefore, to composite above two factors can consider 2 doors controller.
2.3. 2 doors and 4 doors controller can hold a maximum of 20,000 cards and 20,000 lines transaction respectively and perform dynamic adjustment. Single door controller holds a maximum of 10,000 cards and lines transaction and able to do dynamic adjustment.
2.4. 2 doors and 4 doors controllers have more functions; more TTL inputs and outputs; connect RS-485 readers compare to single door controller which can only connect wiegand reader. If were to use Pin open door, can only consider 2 doors or 4 doors controller or all-in-one access controller.
3. Do I need a desktop card reader when issuing cards?
If it is a small system and card reader is not too far away from the computer, during card issuing, can make used of the mounted card reader to read issuing card for it's card number; need not require a separate desktop card reader hence save cost.
If it is a big system, recommend to include a desktop reader for card issuing. If:-
3 bytes EM Card -> SKRD-EM/K2
4 bytes EM Card -> SKRD-EM/K3
3 bytes Mifare Card -> SKRD-MI/K2
4 bytes Mifare Card -> SKRD-MI/K3
4. When a master controller is needed?
Use main controller if it is a huge system. In the absent
of master controller in some situation, a RS-485 line can
only connect up to 32 units controller. Even if uses all
4 doors controller, the entire system can only accommodate
128 doors. If using master controller, the entire system
can expand to 32 x 32 x 4; 4096 doors.
|
