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How does pay by plate work – pt. 2 guide to pay by plate success

Turnkey Parking Solutions Insider Tips

 Complete Guide to Your Parking Technology Road Map.

If you are just joining us, you may want to read Part 1 of this 3 Part Series on the Guide to Pay by Plate Success.

For those of you eager to dive into Part 2, we begin to ‘unpack’ the terms latency and no-communication to shed light on their nuances. Knowing the difference will help you to identify potential road blocks. For non-technicals, you will discover that there are a lot of ‘moving parts’ in a real-time parking rights and enforcement solution. This blog walks you through those nuances so that you will be able to anticipate and circumvent these issues and maximize the tremendous potential pay by plate possesses. Pay by plate is the most influential technology to hit the parking industry since the invention of the coin meter. Understanding it now will position your operation for success today and in the future.

Latency (real time) – For parking enforcement, latency is seen as the time it requires between a parker paying for parking and when that information is available to the PEO for enforcement. How do you handle a parking terminal that pushes transactions to a server late? Generally, no technology is perfect, things will go wrong.

These issues can be caused by several factors:

1.) Wireless coverage issues relating to several factors. As everyone knows from using a cell phone, sometimes moving one foot can mean being able to understand a conversation or not; this same principle applies for pay machines, wireless is not a guarantee and can be affected by reflection from buildings, the weather, foliage to name a few.

2.) Wireless network availability, with cell congestion and the priority that is given to data compared to voice will impact the speed of the network

3.) Speed and availability of Internet / LAN that interconnects all systems (pay by phone, pay by plate kiosk, permits, enforcement system).

4.) Pull technology interfaces not as “real time” as push technology. It is more efficient for the payment manufacturer to push a transaction to enforcement instead of the enforcement constantly requesting “do you have a new transaction”.

Pay by plate latency diagram



No Communication – A system or interface is down which will add to latency. No communication meaning that a system or interface was affected and could not communicate, meaning that the parker is seen as violating during the time the system was down.

1.) Wireless network not available so in this example a pay by plate kiosk is in a situation of no communication because the wireless network is not available

2.) Internet / LAN or interfaces that interconnect systems (pay by phone, pay by plate kiosk, permits, and enforcement) is partially or completely down.

3.) Parking rights payment method is not a real time system. Some systems could have been designed for batch type communication meaning that the information is sent periodically and not immediately when a transaction is done. To better illustrate, here is an example: if a pay by plate kiosk accepts your payment you would expect that the payment transaction be sent in real time. Some kiosk machines on the market are not real-time machines. Meaning that the payment transaction that was accepted has not necessarily been transmitted. So, in essence the kiosk accepts the payment even before any communication attempt was done. If the machine does not accept the credit card payment because there is no communication, that would make it a real time machine.

Human input error – The license plate input from the human point of view from either the parker or Parking Enforcement Officer (PEO) is in error. Human input error or transposition will be seen more from the parker input at a pay by plate kiosk machine. Cities that use pay by plate kiosks should calculate an average of at least 1% error. Furthermore, this error does not improve over time; it actually degrades. With the years of experience we have implementing these technologies we have also noticed that PEO’s can make typing errors; long hours, not paying attention, and bad lighting are some of the many contributing factors that translate to input errors. These errors must be accounted for; in a city the size of Pittsburgh, for example, this could account for over 200 bad tickets a day.

Machine input error – License plate recognition from fi xed, to mobile and handheld are not a perfect science. Read rates typically range from 85% to 95%. Machine input error is categorized as such because it is not the computer making a mistake more than it is the OCR pick up that is in error. LPR OCR stands for optical character recognition and it is the method to translate plate numbers into digital characters. Several things can lower the read rate of LPR like weather (rain, snow, or road salt on the plate), lighting, type of plate and color of characters.

Stay with us for Part 3 of the Guide to Pay by Plate Success as we dive into a detailed solution on tackling these potential pitfalls.


Can’t wait? Request Your Personal Complete Copy of “Your Guide to Pay by Plate Success” now.


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