At present, the use of smart water meters in residential quarters is in the ascendant. In addition to IC card water meters, there are remote water meters, TM card water meters, mechanical card water meters, and RF card water meters (radio frequency meters).
I. Remote transmission water meters are divided into wired remote transmission and wireless remote transmission
Wired remote transmission realizes the transmission of water metering information through water meters, network engineering wiring, multiple sets of signal collectors, and centralized controllers. Network wiring is susceptible to the defect of external lightning, high and low-frequency signal interference of electrical appliances. Both new households and old households must carry out network line engineering construction.
Wireless remote transmission refers to the process of sending water information through remote water meters, and the meter reading personnel of the water management department use the meter reading device to collect water information outdoors.
II. TM card water meter
In fact, it is also an IC (Integrated Circuit) card, except that the general IC card is a five-line card or six-line card, and it is in a standard package, while the TM card is a one-line card with a special package. This kind of card is in direct contact with the device, so the read-write port is generally exposed, and it is more likely to be interfered with by external voltage than the bayonet of the IC card. Therefore, although the TM card is easy to carry (it can be made into a key shape), its security performance (data security and equipment security) is even worse than that of IC card products, and cannot be compatible with the bank's network platform.
III. Mechanical card water meter
The mechanical card water meter, also known as the code table, is a product that uses a mechanical dial card as the pre-purchased water information carrier. The prepaid amount is encrypted and calculated by a computer algorithm to calculate a password. The single-chip computer decrypts and obtains the amount. Due to the cumbersome operation, it is not conducive to computer information management and user control; and there is no storage function of the IC card water meter. The IC card water meter can write the use of the water meter, such as the total water volume, whether there is electromagnetic interference, battery power, whether there is a reverse connection, etc., into the card.
IV. IC card water meter
IC card water meter is a kind of plug-in water meter that is widely used at present. Mainly use the S4442 card (that is, logical encryption card) to realize the data exchange between software and water meter. The advantages are simple operation, pre-collected water fee, no need for manual meter reading, low product cost, and convenient maintenance. It's just that the waterproof performance is not good enough, and the capacity is not as good as the radio frequency card, but it can fully meet the requirements of the property management department at this stage.
V. RF water card (radio frequency card)
RF water card is actually a kind of IC card, referred to as a radio frequency card. Radio waves are used for data exchange, so the electronic control system of the water meter can be used alone, and the waterproof performance is good. The low-frequency radio frequency card (T5557) used in the early stage has no battery itself, and the equipment needs to generate electromagnetic radiation first and provide energy for the radio frequency card through induction electricity. Poor external interference ability.
