Comparison ParkMaster 4FJ-40 vs ParkMaster 4ZJ-51

Working distance range of parking sensors; in other words, this is the interval from the response threshold to the smallest distance at which the device is still able to provide sufficiently reliable data on the distance to the obstacle.

The threshold of operation of modern devices usually does not exceed 3 m, and more often it is in the range of 1.5 – 2.5 m; the sensors themselves are capable of providing a longer range, but in fact there would be little benefit from this, but there are plenty of reasons for unnecessary worries. The minimum distance, usually, is 0.1-0.3 m (10-30 cm); a closer entrance is usually perceived by the device as a close approach, with a corresponding indication (for example, the transition of the sound signal to continuous). And if the response threshold is more of a reference value, then you should pay closer attention to the minimum distance, especially if you often have to deal with cramped conditions (for example, manoeuvring at a difficult entrance to a small garage). Indeed, in such cases, it is important that the parking sensors retain the ability to accurately indicate the distance for as long as possible, without switching to the “close” mode.

Parking sensors with a self-diagnostic function are able to independently detect malfunctions in remote sensors: the device “interrogates” the sensors and, if there are problems, warns the driver. This reduces the risk of being left without a parking radar at an unexpected moment. Usually, self-diagnosis is carried out every time the ignition is switched on.

The diameter of the sensors supplied as standard with the parking radar is an important parameter when installing them: it determines the size of the landing slots, in other words, the holes in the bumper. Many parking sensors are equipped with a special cutter for drilling such sockets — it optimally matches the diameter of the complete sensors, and in this case this parameter actually becomes irrelevant. However, if there is no cutter in the kit, you will not be able to select the drill of the right size without information about the diameter. Also, this information will be very useful if you install parking sensors on a car with existing holes in the bumper (for example, if the previous radar did not suit you according to its characteristics): by choosing a model with the same sensor diameter, you can install them directly into ready-made sockets, without too much fiddling with the fit. So the most popular sensor size is 18 mm, but there are 19, 20, 21 and 22 mm. In this case, often in each option there is a deviation of half a millimetre.

— Digital distance indicator. With this function, the parking sensors not only signal the approximate distance to the obstacle, but display the specific value of this distance in the form of numbers (usually in metres) on the display. Such information is much more accurate and clearer than the data from the LED panel and, moreover, from the sound signaling device.

— Voice notification. This function expands the possibilities of sound signaling: the device can emit not only certain conditional signals, but also voice various information in a voice format. The specific possibilities may be different, depending on the model: some parking sensors speak information about the distance at certain intervals, others specify which side the sensors were triggered from (not only front or rear, but also right or left) and much more.

— Sound volume adjustment. The ability to change the volume of the parking sensors sound signals at your discretion: for example, when parking on a noisy street, increase it so that you are guaranteed not to miss a single notification, and reduce it in a quiet underground garage so that the sounds “do not hit your ears”. In addition, the perception of sounds may differ for different people, and the same signal may turn out to be normal for someone, too loud for someone, and excessively quiet for someone.

— Memory of external elements. Remote elements mean various external parts of a car located in the area of \u200b\u200bbumpers: "reserve wheels", tow bars, "kenguryatniki" grilles, etc. Their location is different, and it is possible that such a part falls into the range of parking sensors and is perceived as an external obstacle. To avoid such false positives, a memory function is provided: the device “remembers” the pattern of the reflected signal from the remote elements, and issues a warning only when real obstacles are within the detection distance.

— Video input (to the camera ZV). A connector that allows you to connect a reversing camera to the parking sensors. This provides a very high degree of control over the situation: if the parking sensors themselves, at best, signal the approximate location of obstacles, then the camera allows you to see what exactly is on the way (moreover, in the “dead zone” right behind the bumper, not blocked by rear-view mirrors). Of course, to view data from the camera, a full-fledged display is required: some parking sensors have their own (see "Indication"), others provide connecting an external monitor via a video output (see below).

— Video output (to the monitor). A connector for connecting a fully functional external screen to the parking sensors — for example, a car TV or a GPS navigator. Usually found among devices with LED bulbs or a sound signal (see "Indication"): much more information can be displayed on an external screen than on standard indicators. However, even in models with their own display, this function may be useful — after all, the capabilities of this display can be much more modest than that of a full-fledged screen.

— Reversing camera included. The meaning of this feature is already clear from the name: by purchasing such a kit, the driver immediately receives both the parking sensors and the rear-view camera, and both of these devices are mutually compatible (whereas when buying separately, problems may arise). Rear-view cameras are used to allow the driver to see blind spots — primarily behind the car (hence the name), but "eyes" are also available for front / side view.