Whelen WPS-2900

The **Whelen WPS-2900** series is a series of modular multicellular electronic sirens that is currently produced by Whelen Engineering, and is the latest version of their omnidirectional sirens. Having been produced for over 15 years, it is Whelen's most popular omnidirectional siren and one of the most popular electronic sirens on the market, rivaling Federal Signal's Modulator and competing with ASC's i-FORCE and ATI's HPSS-32.

Today, the WPS-2900 continues to be sold alongside its sub-models, and is a very popular alternative to Federal Signal's Modulator II and ASC's i-FORCE. It is very popular for cities looking for a high performance electronic siren and do not want to invest in the higher maintenance WPS-4000 series. It is easily Whelen's most popular siren, and continues to have a reputation for high performance and reliability. They can be found worldwide, and rebranded models are sold by HSS Engineering in Europe and the Middle East.

## History and Design

The WPS-2900 was introduced in 2006 to replace the popular WPS-2800 series, boasting several improvements over the latter. The WPS-2900 is largely identical to the WPS-2800, with a few design changes. The most significant is the introduction of Whelen's EZ-Pull drivers, which allow for drivers to be removed and replaced from the side of the siren, instead of needing to partially disassemble the siren to replace a defective driver. This made the siren far easier to maintain. The other design change was the mesh screen, which was reverted back to the same size as the screen on the WPS-2700. This change was made as the enlarged screen on the WPS-2800 created a loud hissing noise when the siren was running due to the vibrations, and the larger screen was not necessary to keep debris out effectively.

The WPS-2900 is otherwise entirely identical to the WPS-2800. It is made entirely of fibreglass, and is made of a varying number of speaker cells. Each cell contains a 400 W "Superpower" speaker compression driver in the bottom half of each cell, which broadcasts the amplified tones from the controller. Each cell is made of two elliptical surfaces, a projector and mesh screen, and six fibreglass supports. This design allows the sound to be projected in a true 360 fashion. The sound is projected upwards from the bottom of each cell, and outwards by a conical projector in the middle of each cell, and by the shape of each cell.

Like the WPS-2800, the WPS-2900 supports between one and ten cells per unit, for a maximum of 4000 W of output. They come standard with the ESC-2030 digital controller, although early units ran on the ESC-2020 controller. The WPS-2900 also includes support for Whelen's VisuAlert, which is a set of 6 LED lights attached to the bottom of the siren to provide visual notification alongside standard audio tones. WPS-2906 and smaller units require a Type II cabinet, while WPS-2907 and above require a Type III cabinet.

The models are as follows:

### Variants

    Also included in the WPS-2900 series is the OmniAlert series. The OmniAlert series was carried over from the WPS-2800, although the models have been renamed. The OmniAlert series comes in one to four cell configurations, designated the OA1, OA2, OA3, and OA4. The OmniAlert series is identical to a standard WPS-2900, but with its voice capabilities removed, meaning it is entirely incapable of relaying voice messages, both prerecorded and live. This reduces the cost of the siren and makes it more affordable for areas where voice is not needed. They are very similar in concept to Whelen's Vortex-R and Hornet.

In 2011, the Firehouse series was introduced. Intended for use by fire stations, it is the spiritual successor to the WS-280 series, which was meant for the same purpose. It is entirely identical to the OmniAlert series, differing only in name and intended market. There are four models in the Firehouse series, the FHS1, FHS2, FHS3, and FHS4.