Moravian Electrotechnic Works

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Moravian Electrotechnic Works (MEW)
Names Moravian Electrotechnic Works

MEW

Headquarters Olomouc, Czech Republic
Founded 1946
Defunct 1950 (Original company)
Products Electric motors

Warning sirens

Moravian Electrotechnic Works (MEW) was the name of an Olomouc, OL-based metalwork company founded in 1946 as a result of the merger of several smaller organizations and produced a variety of products including electric motors and a variety of sirens until its closure in 1950 when the companies affiliated with MEW became state-owned enterprises.

History

Moravian Electrotechnic Works was established sometime in mid-to-late-1946 in Olomouc, OL after the Communist Party of Czechoslovakia won the 1st Czechoslovakian election since the end of WWII. The company was a product of the merger of several smaller companies in Moravia, a region in southern Czechia. In 1950, as part of a "wave" of nationalization, MEW was dissolved by the government and the companies under its umbrella were forked over to the state, becoming national enterprises. Most of them, however, would still retain "MEW" in their name. Most of these companies continued to operate until 1989 when the communist government was deposed during the Velvet Revolution, and they once again became privately owned, and some would end up being purchased by several other companies or renamed.

Products

Type H

Type H 436

The Type H 436, also known as the Type H 436 PO (the difference is unclear), is a small omnidirectional siren, intended for use as a fire alarm or shift change siren. The siren consists of a 4-port rotor and stator and is driven by a 1 ph 220 V 80 W (0.1 hp) motor below the stator, spinning the rotor at around 600 rpm. A circular base below the motor with 4 holes on each side allows the siren to be mounted to a flat surface. The rotor and stator as protected by a mesh screen which prevents injury from misuse of the siren. A rain shield is included above the rotor, supported by a beam above the stator. Units The siren weighs around 5.5 kg.

Type H 584

The Type H 584 is presumably a heavier-duty version of the Type H 436, though this is not known for sure. What the siren looks like is unknown, as very few references to it exist. The siren presumably uses a stronger motor than the Type H 436. The Type H 584 likely did not sell well, as few units, if any, exist today.

Type H/

Type H1/B2

The Type H1/B2 is a medium-sized omnidirectional electromechanical siren and the weaker of the 2 of the H/ series. The Type H1/B2 consists of a 9-port rotor and stator and is driven by a 380/400 V 1 or 3 ph 1.1 kW (1.5 hp) motor beneath the stator, spinning the rotor at around 2800 rpm. A circular base below the motor with 4 holes on each side allows the siren to be mounted to a flat surface. The siren can be told apart from the Type H4/A2 by the thinner motor. A large rain shield made of sheet metal is suspended above the stator via 6 supports. The space between the stator and the rain shield is protected by a mesh screen, as well as the stator itself. 2 louvers, which are also made of sheet metal, are located above and below the stator to project the sound downwards; the siren was also offered either with only the top louver or none at all. Some units are known to have no rain shield or louvers, though this was likely not a factory option and chances are they just rusted away. The siren weighs around 52 kg. The Type H1/B2 is often used as a fire siren today and is one of the most common sirens in Czechia, alongside the Type H4/A2.

Type H4/A2

The Type H4/A2 is a medium-sized omnidirectional electromechanical siren and the heavier-duty version of the Type H1/B2. The Type H4/A2 consists of a 9-port rotor and stator and is driven by a 220/380 V 1 or 3 ph 4.5 kW (6 hp) motor beneath the stator, spinning the rotor at around 2800 rpm. A circular base below the motor with 4 holes on each side allows the siren to be mounted to a flat surface. The siren can be told apart from the Type H1/B2 by the wider motor. A large rain shield made of sheet metal is suspended above the stator via 6 supports. The space between the stator and the rain shield is protected by a mesh screen, as well as the stator itself. 2 louvers, which are also made of sheet metal, are located above and below the stator to project the sound downwards; the siren was also offered either with only the top louver or none at all. Some units are known to have no rain shield or louvers, though this was likely not a factory option and chances are they just rusted away. The siren weighs around 110 kg. The Type H4/A2 is often used as a fire siren today and is one of the most common sirens in Czechia, alongside the Type H1/B2.