Meters 101 ... a crash course!  I certainly hope not!  Hang up and drive!    -Fred Stock

Centrodyne 610 - Industry Standard       Pulsar 2030 - excellent slim line unit . . . . . . Just introduced Centrodyne S700

Definition: Taxi Meter; n. a device in a vehicle for hire which accurately determines the distance traveled by the vehicle and generates fare information and statistics. Taxi meters are regulated by the federal government under the National Institute of Standards and Technology (NIST) and type accepted before these devices are sold or used in the United States. Their features are also prescribed by NIST regs.

Who Needs a Taxi Meter? According to the regulations, if you are selling your service by a unit of measure, the measuring device must be certified and type approved. This means if you do fares by the mile or kilometer, you must use a type-approved taximeter, (such as the Centrodyne line we handle). If you are selling fares by "zone" ("I'll take you to the airport for 38-bucks") then you don't need a meter, but you generally must post your zone charges in the cab. To be safe and legal, use a meter, be sure it is calibrated properly, and have it inspected by your local "weights and measures" office before starting to use it. In most places, they will "seal" the meter to prevent changes after the inspection.
(Questions? Call 760-345-4347
Logan2 or e-mail )

A taxi meter can accumulate charges (fares) in three ways;

    1) distance traveled in the "hired" (on) mode. The meter is connected to a device within the vehicle - normally a vehicle speed sensor or distance sensor today - which provides information on distance traveled via pulses corresponding to revolutions of the transmission, axle or transaxle. The meter, a small computer, uses this information to establish the actual distance traveled, and computes the fare based upon a program fixed in the meter, and calibration information relating the meter to the exact vehicle in which it is mounted. (++ SEE BELOW for an additional word about pulses and distance. ++)

    2) time accumulated in the hired but stopped mode. ("waiting time") The vehicle is considered stopped when the vehicle is traveling less than approximately 12 miles per hour. This allows the grid locked cab to make money based on time whilst creeping along, and to allow the meter to run while the cab is stopped, as in a brief stop at a store, or "Wait here, I'll be right out" situation. The fare is then based upon a programmed amount of money per increment of time - perhaps 20-cents every 58 seconds, etc.

    3) flat rate charges called "extras".  There is a feature called "Extras" in modern meters. A single flat rate can be programmed and added to the fare with a touch of a button marked 'extras" on the meter face. These can be used for fees required, such as Airport Fees, toll bridge charges, or similar recurring fees. One company is located a hour from a military base, and frequently takes servicemen from the train or airport to the base and comes back empty. He has a $14.00 "one way" fee clearly posted in the cab, and presses the "extras" button to activate the fee. Only one value can be set into the meter (per rate) for this use.

Meters sold in the USA generally are capable of four or more rates (some even 16 rates) - that is, entirely different sets of charges and fees for geographic areas. Suppose you are located near a large city and have a local clientele who regularly use your service. The locals may pay 1.50 per mile and a waiting time of $15.00 per hour. But when you are operating in Metropolis, the city requires you have $2.00 per mile and $25.00 waiting time. Your meter then, should be programmed for two different rates, one for local use and one for Metropolis. You select the rate before turning on the meter (select with a button on the front of the meter.) You might have NO extras on rate 1, but an airport charge of $5.00 required by the city regulations. So only rate two would have the $5.00 extras programmed. Your meter is after all, a computer, and can be programmed within limits, to do many different things. Ask us for special cases.

Some newer meters are capable of up to 8 rates! And in certain locations, like New York City, leasing time-outs, special date-related rates and automatic even changes to rates fore different times of day need to be set into your meters. Meters for most places are not nearly so complex. Ask us !

Meters must be able to be sealed via a lead wire or plastic numerically serealized devices (seals) to prevent tampering.

A modern taximeter can provide many features which the industry has come to expect.

First, the BASIC TAXI METER.  Features:

. . . . . . . . .
1) Clearly displayed fare.
                2) Clearly Displayed Extras (separate from fare. At the end of the trip, a button will add the two screens together for a few seconds to prevent math errors, then split them back apart [per federal regulation].)
                3) Indication of the status of the meter: HIRED or VACANT, TIME OFF (when stopped but NOT charging the client for the time).
                4) Statistics (permanent stats which the driver cannot reset or change, like your odometer in the dash). These include the Money Total, Extras $$ Total, Distance traveled TOTAL, Distance traveled WHILE HIRED, trip count (number of times the meter has been turned on to "hired".)   
(In Canada a tax is applied to distance, and this is accounted in the statistics there.) [FYI:  In certain cities like New York City, there are special conditions such as rates which change with time of day or day of the week, special holiday rates and so forth, all of which can be programmed into specially ordered meters.]

  5) Taxi meters are capable of controlling via a relay, the lamps and indicators in or on the toplight or sign. This means a visual indication for the condition of the meter can be placed in public view. In Palm Desert California, for instance, the toplight is required to display a "VACANT" sign lighted when the meter is NOT hired, but the ignition switch is turned on. Then the Vacant goes out and the AMBERS are lighted when the meter is hired. This feature is NOT REQUIRED in all places, but it is available on all meters we sell. Many areas switch the top sign OFF when the meter is hired, and light it when vacant (available).

FNY4 6) Some areas, such as New York City, actually have amber markers on each end of the meter, which can be connected to the turn lights or other circuitry! These are not controlled by the meter, obviously, but the inner sign has "OFF DUTY"/"ON DUTY"panels and a center panel which can be driven from a relay controlled by the meter. We sell the meter shown here with the same feature, but no ambers. Call us for details and options. (760-345-4347).

P2030R Second, the PRINTING TAXI METER. Has all the features of the basic meter plus a printing function. This meter has a Built-In calculator sized printer, capable of printing a receipt for the customer, and printing out stats for the operator.


S700 meterJune 2011 Update: Here is a new type of meter. It has the same basic usage features, except it has virtually unlimited expandability. In older meters, the "firmware" inside the meter was made for a basic meter. When you wanted to add a printer, you added a special cable by making wiring changes in the connecting terminals, and you replaced the firmware chip inside the meter. That could run into hundreds of dollars in addition to the printer itself. In this new S700 meter, all the connections are on little plugs inside the mounting base. The meter also comes with the firmware for every known use already built in. All you buy is an inexpensive cable which plugs in without changing anything in the meter, and of course you buy the printer. It takes about 5 minuites to get it in and working. That holds true for all kinds of add-on gadgets like credit card processors, communications devices like MDT's and so forth. .

Finally, a new generation of devices is emerging with a variety of new interfaces. The meter can be integrated into a dispatch system which can display destination and other information for the driver, track the cab's response and location, create signals that allow a camera to record the riders and remember their faces and actions. The industry is developing quickly as are most technological fields today.

++  Some additional ideas about pulses and distance calculations:

First of all, the only way a taxi meter can work today in the USA is by getting information from the car on the distance traveled. These are generally pulses (or sine waves more recently). These come from the vehicle speed sensor on current vehicles, or from a transducer.

A transducer is a mechanically driven device that revolves, riding on the old mechanical speedometer cable. This turns a tiny wheel inside the transducer,  carrying a set of magnets past a sensor – usually a “reed switch” or optical switch transistor – which produce switched ground signals for the meter – that is, "pulses". 

Another method of extracting information is from a computer device which records revolutions of the drive shaft. Since there isn’t a speed sensor on older cars (pre-1992 approximately), you have to either interrupt the speedometer cable assembly and install a transducer, or create a pickup system on the axel or drive shaft to create pulses. There isn’t any other way. Someday we will probably work from GPS signals for distances, but not today. You can mount our pick-up kit on the drive shaft or preferably the axel. Then you mounting a sensing device we provide, which will change the magnetic fields into electrical pulses. There is no standard type of mount – rather, you must fabricate a mount for your exact car. I wish there were an easier way but there is not. Your best bet is to have a dependable speedometer shop install a transducer for you. We can provide the parts and you can find shop that has a hydraulic press for making up the cable ends. This will create a dependable pulse output and your meter will work properly.

The most efficient approach is to start out with a vehicle that has a pulse system in place - from about 1995 to 2003 model years are generally OK, and in the commonly used Taxi Vehicles such as the Ford Crown Victoria's, Mercury Grand Marquis, Lincoln Town Cars, GMC Safari, Ford Aerostar, Chevy Caprice or Malibu, etc. They are fitted with devices which can be tapped for the pulse without problems. If you have a question about a vehicle you are considering, feel free to call us and ask. Be aware of the newest trend in automotive information flows, the Local Area Network. Computer devices are located around the vehicle and the data is shipped about the car through a "computer bus" wiring system. The pulses we need DO NOT EXIST. We are working on a set of devices which will decode this data for you - in fact we have one available now, but it is quite expensive! More on that when we have the answer and a good price.

Laws and Requirements.

Regulatory bodies in some cities and municipalities are financed by a surcharge on taxi activity. They regularly read the trip count of the taxi cabs in their area, and charge the drivers or owners by the trip. Some cities levy a tax similar to the Canadian taxes, and require special programming in all the meters to facilitate the record keeping. Many areas require their meters be sealed after calibration. A licensed agent is required to test the accuracy of the meter settings and place a seal such as a lead wire device (similar to your electric power box seal) on the meter. If the seal is broken, the meter is no longer legal for use until it is rechecked and resealed.

Taxi meters are "type approved" by the federal government before they are offered for sale or use in the USA. The National Institute of Standards and Technology (NIST) Handbook 44 regulations are the standard for the United States. [See and read section 5.54 Taxi Meters.] Most states "carbon copy" these regulations, and most county governments are charged with enforcement and inspection of the meters.





About programming and calibration:

          There seems to be some confusion about PROGRAMMING and CALIBRATION of your taximeter. Let’s define both and note the differences.

PROGRAMMING: Your taximeter is a small computer. It cannot do anything by itself until it is “programmed” with your rates, charges, fees and information about HOW the money is to be calculated. You tell it things like the Initial “flag drop” fee, the amount you charge per mile, what increment of coinage is to be registered (like 25-cents per tenth of a mile), how much to charge for waiting time, etc.. Programming also sets up such things as multiple rates if needed, lease time-outs, special circumstances for changing rates, etc. Most meters are quite simple. If they are purchased from Fred Stock Electronics or, they arrive at your door already programmed with your information (providing you have given that to us.) Your meter must be programmed in order to work.

THE CONCEPT OF CALIBRATION:  Suppose you were to glue an endless number of yardsticks to the curb. Now, as you drive up the block, as you pass the end of each yard stick some sort of signal occurs in your car. Obviously, the faster you go the faster would come the pulses, and the further you travel, the more of them would accumulate if you were counting them. This is very close to what happens in your car. You may never have noticed all those yardsticks on your street, but they are there... 'er no, that's not right... In your car there is a device which makes pulses of electricity which accurately represent the distance you have traveled. These pulses are used in the generic vehicle by such equipment as transmission control computer, cruise control, speedometer/odometer, even the music radio gets these pulses in some cars which actually turn the radio down a little when you are stopped at a signal, and back up again when you start moving again. We can tap into this source in most vehicles and feed the pulse train to our meter. Now the meter gets an unknown number of pulses per mile. When we "calibrate" the meter, we simply drive the car for one EXACT 5280 ft mile (or kilometer if your area uses metric measurement) andwe tell the meter to count the pulses it sees. Then we lock that number in. Suppose the meter counts 2060 pulses in a mile (or km). Then later when you are operating it sees 4060 pulses. It then knows it has moved two miles (or km's) and does the math to calculate the fair. It's a computer so it can do that. Notice it doesn't care whether it is being calibrated in miles or kilometers; You have programmed the meter to charge perhaps 2.50 per 100% of the distance represented by a certain number of pulses. If that's a KM it will charge that after one KM, and if that's a mile, it does it after one mile. It only cares how many pulses it has counted. WE care whether they mean KM or MI but the meter only thinks about counts. All we have to do is get the correct number of pulses into the meter when we calibrate. They can represent miles, kilometers or klepinschlimers, if your area has invented those!

CALIBRATION: Once the meter is installed in your car, and connected properly including a source for measuring travel activity, it receives data from your car on the actual distance you have moved. Understand, the meter needs to know exactly how many pulses are sent to it in the distance of one exact mile (or kilometer if that is your local system.) This is accomplished by “calibrating” the meter. This is usually accomplished by driving an exact measured mile with the meter in “counting” mode. Then you enter the information into the meter computer memory, in effect telling it, “expect this many pulses in one mile.” It then applies the program already in the meter, and produces your fares and other information. It is illegal to operate a meter which has not been calibrated to the vehicle’s systems. Most places, you’ll then need to take it to “weights and measures” or a regulatory agency or police inspector to be inspected and “sealed”.