PositioningUnit RPU

The RPU Ridder PositioningUnit is a high-accuracy digital positioning meter for use in in Ridder RW motor gearboxes, making it the perfect solution for obtaining accurate positioning data for ventilation, protection and lifting systems. The current position is monitored continually by the RPU and the position is fed back to a climate regulator using a 4-20 mA signal. The RPU can be used with all types of Ridder RW motor gearboxes that are fitted with a Ridder RSU end switch system. The RPU can be supplied individually or built into an RW motor gearbox.

The 4-20 mA signal from the RPU is generated using a Hall sensor built into the RPU and a magnetic axis mounted above it. The magnetic axis rotates contact-free and is mounted on the limit switch shaft of the RSU end switch system in a Ridder RW motor gearbox. This contact-free measuring technology means that the RPU’s feedback signal value always remains constant and that the RPU requires no maintenance. During operation, the RPU measures the position continuously with a high degree of accuracy - 0.04% of the measuring range that has been taught in. From this measuring signal, the RPU calculates the 4-20 mA signal that needs to be fed back. This signal is reversible. Using an ohmic resistor, a 0-5 V or 0-10 V feedback signal can also be generated. The RPU is equipped with an operating button and LEDs so that its status can be read easily.

The RPU is easy to install and easy to "teach in". Normally, the measuring range to be taught in will correspond to the switching range of the RSU end switch system. The end positions taught in for the measuring range of the RPU (SP1 and SP2) will then correspond to the end positions of the RSU (ES11 and ES12). It is also possible to set one of the end positions for the RPU’s measuring range as an end position for the end switch system. The RPU’s measuring range will then be smaller than the switching range of the RSU end switch system. This is one solution for systems with a switching range that is larger than the measuring range of the RPU that is being monitored (between SP1 and SP2). This option also makes it possible to teach in RPUs with an identical measuring range for independently driven systems with different switching ranges for the end switch system.

While in operation, the quality of the signal is monitored constantly by an integrated reference monitor. If there is an external disruption, such as a loss of power, the value measured by the RPU will deviate from the expected value and the RPU will generate an error message as a result. A 0 mA value will then be fed back and a blink code will be displayed.

In order to carry out a reset after a reference deviation, the RPU is equipped with a reference input. The reference input can be connected to a duty switch in the RSU end switch system. By operating this duty switch in an end position, the reference deviation and the error message that it has generated will reset automatically. However, the switch position of this duty switch must correspond to the end position of the measuring range taught into the RPU.

The RPU PositioningUnit can also be installed and taught in in such a way that in the event of a reference deviation, the reference reset will occur through range recognition. The RPU can do this without a duty switch being connected to the reference input. However, in this case the entire measuring range taught in will then have to be travelled through to carry out the reference reset.