The difference between fixed code (PT2262) and learning code (Ev1527)
Nowadays many people are afford to get a burglar alarm system for their home and business. Before make decision on purchasing burglar alarm system, some people may not understand what the fixed code is for alarm system or what the learning code is.
What’s the difference between fixed code and learning code? Which one is better?
Fix Code:
IC: Encode chip PT2262 (Traditional wireless detectors)
Decode chip PT2272 (Traditional wireless alarm control panel)
Address: 3 to the 8th power (6561 unique addresses).
Features:
1.Security level not high, few addresses may cause duplicate address code. This may cause false alarm.
2.It’s very difficult to increase (add) extra wireless detectors or sensors for user. The theory of fixed code is that the address of detectors (encode) must match the address of alarm control panel (decode). If want to increase the detector, you need to know the alarm control panel address. By the way, encode address need user to have some basic knowledge of electronic technology.
3.It’s a terrible thing, if lost the remote controller (keyfob). Because alarm control panel can not delete the address (or detectors), people pick up the remote controller can freely control your alarm system; If ask user to change the address of alarm system, that’s troublesome, you may need to set all the wireless detectors and sensors, as well as detectors match the new address of control panel.
Learning Code:
IC: eV1527
Decode: MCU
Address: 2 to the 20th power (1048576 unique addresses)
Features:
1.High security level, 100 million addresses decrease the duplicate address rate.
2.It’s easy and convenient to add and delete the wireless sensors and detectors. All the wireless detectors and accessories using different address code, you just need to learn them into alarm system.
Don’t worry when you lost the remote controller (keypad), you just need to delete it from alarm control panel, then that remote controller is not able to communicate with alarm control panel, and it’s useless, can not control the alarm system any more.
| Type | Typical IC | Encoding Method | Security | Price |
|---|---|---|---|---|
| Fixed Code | PT2262 | Manual Encoding, using dip switch or soldering to set address code | Low | Low |
| Learning Code | EV1527 | Automatic Encoding, copying fixed code or learning code remote | Medium | Medium |
| Rolling Code | HCS301 | Automatic Encoding, using algorithm to generate different code every time | High | High |
Rolling Code is widely used in Car Alarm System
The typical oscillator resistor value of EV1527 chip is 300 K, 330 K, 360 K, 390 K and 430 K. Commonly an EV1527 chip with 300 K oscillator resistor can pair with PT2262 chip with oscillator resistor values ranging from 1.5 M to 4.7 M.