SLEA
| Siren Loudspeaker Single Axle Trailer
Sirene-Lautsprecher-Einachs-Anhänger (SLEA) | |
| |
| Company | HELIN |
|---|---|
| Produced | 1952-1962/3? (SLEA 52)
1962/3?-1965 (SLEA 62)
|
| Type | Omnidirectional Engine-Driven Electromechanical/Electronic |
| Horsepower | 1.4 kW (1.8 hp, siren)
5.2 kW (6.9 hp, engine)
|
The Siren Loudspeaker Single Axle Trailer (German: Sirene-Lautsprecher-Einachs-Anhänger, abbreviated SLEA) refers to 2 omnidirectional mobile gas-powered mechanical sirens produced by HELIN from 1952 to 1965. These were intended for use in the event power would not be readily available or reliable. Several SLEA sirens can still be found today, with a very small amount still in service as fire sirens and most in the hands of private owners. The SLEA was one of HELIN's last siren ventures until the mid 2010s, when they once again forayed into the siren market with brand-new lines of electronic sirens that are still produced today.
Design
SLEA 52
The Siren Loudspeaker Single Axle Trailer 1952 (German: Sirene-Lautsprecher-Einachs-Anhänger, abbreviated SLEA 52), at its core, consists of a DS55 (which seemed to have been made specifically for the SLEA but could be ordered separately if desired), a small omnidirectional 220/380 V 1.4 kW (1.8 hp) siren modelled after the L52 with minor differences. The DS55 is 39 cm (15.3 in) in diameter and weighs around 35 kg 77.1 lbs[1]. Also included are 2 speakers mounted on each side of the siren unit. These are mounted above a large trailer with a viewing window. A door is located on the side of the trailer, allowing for access to the internals. The assembly is attached to a chassis with 2 wheels attached to it. The speaker units were manufactured by Siemens and Halske, while the trailer is a product of Westfalia and Wiedenbrück. Inside the trailer are the controls for the siren and speakers and a generator, powered by a 3ϕ 380 V 2-stroke, 5.2 kW (6.9 hp) ILO L 250 engine, which drives the siren. Also included inside the trailer are storage compartments under the roof for cables and spare parts, a spare wheel and a drawbar. On the door is a compartment for the remote control and several other tools. The engine has a fuel tank capacity of around 6.5 l. This engine could also be used for other purposes when the siren/speakers were not in use. The speakers' controls would be housed inside the vehicle towing the unit as well as a microphone, allowing for the driver to deliver voice announcements. The SLEA 52 was painted in a variety of different colors depending on what organization owned the siren; for instance, units owned by the Federal Office of Civil Protection and Disaster Assistance (German: Bundesamt für Bevölkerungsschutz und Katastrophenhilfe, abbreviated BBK) were orange, units owned by the Federal Agency for Technical Relief (German: Bundesanstalt Technisches Hilfswerk) were blue, and units owned by the fire defense (German: Feuerwehr) were red. Very few SLEA 52 sirens have remained in their original colors.
SLEA 62
The Siren Loudspeaker Single Axle Trailer 1962 (German: Sirene-Lautsprecher-Einachs-Anhänger, abbreviated SLEA 62) was introduced in 1963 as an improved version of the SLEA 52 with minor changes. Like the SLEA 52, it consists of a HELIN DS55 with 2 speakers mounted on each side of the siren unit, mounted above a large trailer on a chassis with 2 wheels. Inside the trailer are the controls for the siren and speakers and a generator, powered by a 3ϕ 380 V 2-stroke, 5.2 kW (6.9 hp) ILO L 250 engine, which drives the siren. Also included inside the trailer are storage compartments under the roof for cables and spare parts, a spare wheel and a drawbar. On the door is a compartment for the remote control and several other tools. The engine has a fuel tank capacity of around 6.5 l. This engine could also be used for other purposes when the siren/speakers were not in use. The speakers' controls would be housed inside the vehicle towing the unit as well as a microphone, allowing for the driver to deliver voice announcements. Like the SLEA 52, the SLEA 62 was painted in a variety of different colors depending on what organization owned the siren. The most notable visual changes include the door on the side of the trailer being removed and replaced by 2 doors on the front and rear of the trailer, the addition of an angled viewing window also on the trailer's rear, and the inclusion of a large fan on the trailer's front end to provide sufficient ventilation to the inside and prevent any of the components from overheating, as the SLEA 52 was known to have ventilation issues. The fan is protected by a circular cover, bolted on to the trailer. 2 extendable support legs located at the trailer's rear are also included. Some of the parts used for the unit's internals were replaced with different ones, manufactured by Kaiser. Several compartments inside the trailer are also rearranged. The speakers manufactured by Siemens were switched out for plastic ones made by Telefunken to make the overall assembly lighter in weight. A few largely un-notable changes in the trailer's construction are also apparent. Aside from these changes, the SLEA 62 and SLEA 52 are relatively identical.