Southern California Edison Model 120: Difference between revisions

	Southern California Edison Model 120
	; A Model 120 unit on a Sentry mount.
Company	Southern California Edison
Produced	1982-1988
Type	Supercharged Electromechanical Omnidirectional Pneumatic
Sound output	120 dB @ 100 ft
Horsepower	2 hp (chopper) 10 hp (blower)

VisualWikitext

Latest revision as of 20:49, 19 August 2024

The Southern California Edison Model 120^[1], also known as the SoCal Edison Model 120 or simply the Model 120, is a 120 dB low tone supercharged electromechanical siren that was designed in-house by SONGS audio engineer John Glenn Powell specifically for use within the 10 Mile Emergency Planning Zone (EPZ) for the San Onofre Nuclear Generating Station (SONGS) during its operating life. It is one of a few examples of a siren that was purpose-built for a system.

History

The Model 120 was created in 1982 as a custom-built siren for the SONGS plant, which had strict requirements for its siren system. SONGS had gone through two other systems before this point, with a system of 39 Sentry sirens originally being installed in August 1981 and tested in January 1982. The Sentry sirens were found to perform worse compared to what was advertised, leading to the sirens being removed. SONGS would then install a new system of 39 Federal Signal STL-10s, with those being installed by April of 1982 and tested in May of the same year. While the STL-10s performed significantly better than the Sentry sirens did, they still didn't meet the plant's needs, with insufficient coverage and a lack of corrosion resistance.

The only sirens on the market at the time with enough range that would meet the plant's needs at the time were rotational, but SONGS wanted to use exclusively omnidirectional sirens to reduce maintenance costs. Some of ACA's omnidirectional sirens, such as the Cyclone, were likely considered but did not meet the requirements either. With a lack of available options, SONGS opted to design and create their own siren to meet their requirements. The job of designing the siren was given to SONGS' audio engineer, John G. Powell, who created a compact, high-performance omnidirectional siren design using massive horns and a centrifugal blower. After being inspected by the plant, the siren was green-lit for production. Starting around June 1982, Model 120 prototypes started to be constructed and tested, with the final units being completed in March 1983.

Originally, the plan was after the first Model 120s were installed, a total of 52 additional Model 120s were going to replace the existing Federal STL-10s and make the system entirely Model 120s. This plan was dropped shortly afterward due to the increasing delays and costs caused to the plant by not having a ready siren system by 1981 which was the original year planned for the plant's 2 newly constructed reactors to begin operating. Units #2 and #3 were ready to begin operation, but because the siren system was inadequate, they couldn't begin operation until the Model 120s were installed. This caused a delay for over a year, as it also happened around the same time the NRC required nuclear plants to have siren systems. This also meant the plant's existing Unit #1 could not be restarted until the siren system was ready. There were 22 of these sirens produced, with one being never installed and put into storage as a spare.

16 of these were installed in October 1982 to add into the system of STL-10s, 8 of which indirectly swapped out with Model 120s with another 8 being brand new installs. 5 additional sirens were installed in 1988, one of which replaced a Federal Signal Thunderbolt that was an existing Civil Defense siren. After the Model 120s went up, to end the delays of the siren system not being up to par, SONGS opted to keep the remaining STL-10s and add 21 Model 120s in areas that need coverage to get the EPZ up to code for the plant's reactors to start. After a successful system test in July 1983, the plant's new reactors began operation shortly afterwards with Unit #2 starting on August 8th, 1983, and Unit #3 on April 1st, 1984, as well as Unit #1 being restarted. These delays and the cost of the sirens themselves cost the plant over $1,000,000.

By June 2004, the plant began discussing a system replacement project due to the sirens suffering from advanced corrosion and degrading reliability due to the system's proximity to the ocean. A year later, beginning in November 2005 (a month after the annual siren test), the Model 120s and the STL-10s started to be gradually removed and replaced. By February 2006, all had been replaced by Whelen WPS-2810s and WPS-2806s that were installed in their places. The 2810s replaced the Model 120s and the 2806s replaced the STL-10s. These new electronic sirens had battery backup and voice capability (that was never used), were much lower maintenance due to their corrosion resistance, and had similar ranges to the sirens they replaced. These new sirens met the strict requirements of the plant without the need to specifically design a new siren. These would be later removed after SONGS was decommissioned. After all the old sirens had been replaced, SONGS sold 23 of the STL-10s to Curry County, Oregon, to be used as tsunami sirens, and the Model 120s and remaining 5 STL-10s were scrapped, save for a single Model 120 that was never installed, kept as a spare for parts and forgotten about. This last remaining unit is currently in private possession by Duderocks5539, undergoing restoration to eventually make it fully operational.

Design

The Model 120 is a unique mix of a supercharged and pneumatic electromechanical siren that lacks any vanes on the rotor, meaning it requires an external air source to produce any meaningful sound. The sound is created by a 4-port (later 5-port) single-tone rotor, which spins inside the stator and acts as a chamber to contain the air inside. The rotor is driven by a 2 hp TEFC AC motor that runs at 3450 rpm, driving the siren from above. The siren has an 8-port stator, and the sound is then projected by 8 large fiberglass horns attached to the stator. The siren makes use of a belt-driven Paxton centrifugal blower, that uses a 10 hp TEFC motor which sits below the siren's head to force pressurized air up into the rotor. This is a similar configuration to the Japanese Hankoku siren, which also uses a centrifugal blower below the siren.

The 4-port units reached a frequency of 240 Hz (480 Hz without the blower due to the lack of air resistance making the rotor spin faster) and the 5-port units reached 300 Hz, or 600 Hz without the blower. The rotor and stator are both coated in Teflon, which helps seal the air in and prevent leaks, while also helping to protect them from corrosion from the salty air. The Model 120 is massive in size, requiring a significant framework to hold up the siren's massive fiberglass horns, as well as the blower and the rotor/stator itself. The siren was designed for being mounted on poles rather than rooftops, attached to the pole either through a custom mount, or reusing the mounts from the Sentry sirens they replaced.

Gallery

7 Model 120 heads and blowers prior to being assembled.
Assembled unit without horns.
Horns being attached and conduits ran to main junction box.
5 out of the 8 horns attached with another unit being assembled off to the left.
Closer view of the head with the siren 95% assembled.
Fully assembled Model 120.
Fully assembled Model 120 with the other 6 being assembled and crated up to be transported to San Onofre Nuclear Generating Station for installation in the 10 mile EPZ in October 1982. These were the first 7 to be installed which replaced 7 STL-10B's.
Siren Location SC-13 illuminated by a spot light at night in 2003. The siren was 21 years old at the time.
Head of the privately owned unit with a salvaged motor attached.

@@ Line 1: / Line 1: @@
 {{Infobox siren
-|image =[[File:Model 120.jpg|Unit installed on a wood pole]]
+|image =Model 120.jpg
 |company= Southern California Edison
-|produced= 1983 and 1988
+|produced= 1982-1988
-|type=[[Pneumatic]]
+|type=[[Supercharged]] [[Electromechanical]] [[Omnidirectional]] [[Pneumatic]]
-|output=120
+|output=120 dB @ 100 ft
-|hertz = 300
+|hertz = 240 or 300
-|neigh = 2 (Rotor) 10 (Blower)
+|caption=A Model 120 unit on a Sentry mount.|hp=2 hp (chopper)
-}}
+hp (blower)}}
-The ''' SoCal Edison (SCE) 120 ''' or ''' Model 120 ''' was a 120 dB low tone pneumatic siren designed in house by Southern California Edison for use within the 10 Mile Emergency Planning Zone (EPZ) for the ''' [[San Onofre Nuclear Generating station]] '''.
+The '''Southern California Edison Model 120'''<ref>While Southern California Edison Model 120s are often referred to as "Toshiba" sirens by enthusiasts, these were not made by Toshiba. These were purely a custom-made design built in-house by Southern California Edison.</ref>, also known as the '''SoCal Edison Model 120''' or simply the '''Model 120''', is a 120 dB low tone supercharged electromechanical siren that was designed in-house by SONGS audio engineer John Glenn Powell specifically for use within the 10 Mile Emergency Planning Zone (EPZ) for the San Onofre Nuclear Generating Station (SONGS) during its operating life. It is one of a few examples of a siren that was purpose-built for a system.
 == History ==
-There were 22 of these sirens produced with one being never installed which is now privately owned. 16 were installed in July 1983 to add into a system of 39 Federal Signal STL-10s that were installed in April 1982, 8 of which indirectly swapped out with Model 120s with another 8 installed as new locations, and later in 1988 5 additional locations were installed, one of which replacing a Thunderbolt that was actually a CD siren used by one of the cities before SCE took over it for use in their siren system.
+[[File:Model 120 prototype being mounted to an existing STL-10 pole for range and output testing in 1982.jpeg|thumb|left|upright|Model 120 prototype being mounted to an existing [[Federal Signal STL-10|STL-10]] pole for range and output testing in Summer 1982.]]The Model 120 was created in 1982 as a custom-built siren for the SONGS plant, which had strict requirements for its siren system. SONGS had gone through two other systems before this point, with a system of 39 [[Sentry Siren|Sentry]] sirens originally being installed in August 1981 and tested in January 1982. The Sentry sirens were found to perform worse compared to what was advertised, leading to the sirens being removed. SONGS would then install a new system of 39 Federal Signal [[Federal Signal STL-10|STL-10s]], with those being installed by April of 1982 and tested in May of the same year. While the STL-10s performed significantly better than the Sentry sirens did, they still didn't meet the plant's needs, with insufficient coverage and a lack of corrosion resistance.
-The reason these sirens were made is because there was no other siren available that would meet the plants needs, the system first started out with Sentry 10V's, 5V's, and 3V8's installed in August 1981 and was tested January 25th thru 27th, 1982 and proved to preform extremely poorly and the discussion was made to swap the 39 Sentries out for STL-10s by April 1982 with testing of them commencing by May the same year. STL-10 performance was significantly better, but still not good enough coverage wise. The only sirens that were available on the market that have the range the plant was looking for were rotating directional sirens only, of which the plant wanted Omnidirectional only sirens. So the decision was made to design their own siren.
+The only sirens on the market at the time with enough range that would meet the plant's needs at the time were rotational, but SONGS wanted to use exclusively omnidirectional sirens to reduce maintenance costs. Some of [[Alerting Communicators of America|ACA's]] omnidirectional sirens, such as the [[ACA Cyclone|Cyclone]], were likely considered but did not meet the requirements either.  With a lack of available options, SONGS opted to design and create their own siren to meet their requirements. The job of designing the siren was given to SONGS' audio engineer, John G. Powell, who created a compact, high-performance omnidirectional siren design using massive horns and a centrifugal blower. After being inspected by the plant, the siren was green-lit for production. Starting around June 1982, Model 120 prototypes started to be constructed and tested, with the final units being completed in March 1983.
-[[File:Model 120 prototype being mounted to an existing STL-10 pole for range and output testing in 1982.jpeg|thumb|left|upright|Model 120 prototype being mounted to an existing STL-10 pole for range and output testing in 1982.]]
+Originally, the plan was after the first Model 120s were installed, a total of 52 additional Model 120s were going to replace the existing Federal STL-10s and make the system entirely Model 120s. This plan was dropped shortly afterward due to the increasing delays and costs caused to the plant by not having a ready siren system by 1981 which was the original year planned for the plant's 2 newly constructed reactors to begin operating. Units #2 and #3 were ready to begin operation, but because the siren system was inadequate, they couldn't begin operation until the Model 120s were installed. This caused a delay for over a year, as it also happened around the same time the NRC required nuclear plants to have siren systems. This also meant the plant's existing Unit #1 could not be restarted until the siren system was ready. There were 22 of these sirens produced, with one being never installed and put into storage as a spare.
+of these were installed in October 1982 to add into the system of STL-10s, 8 of which indirectly swapped out with Model 120s with another 8 being brand new installs. 5 additional sirens were installed in 1988, one of which replaced a Federal Signal [[Federal Signal Thunderbolt|Thunderbolt]] that was an existing Civil Defense siren. After the Model 120s went up, to end the delays of the siren system not being up to par, SONGS opted to keep the remaining STL-10s and add 21 Model 120s in areas that need coverage to get the EPZ up to code for the plant's reactors to start. After a successful system test in July 1983, the plant's new reactors began operation shortly afterwards with Unit #2 starting on August 8th, 1983, and Unit #3 on April 1st, 1984, as well as Unit #1 being restarted. These delays and the cost of the sirens themselves cost the plant over $1,000,000.
-Starting in around June 1982, Model 120 prototypes started to be constructed and tested, with the final designed units being completed in March 1983, originally the plan was after the Model 120s were installed, a now total of 52 sirens were going to be all Model 120s which means swapping out the remaining STL-10s with 120s making the system Model 120's only, but this plan was dropped shortly afterwards and only about 8 Model 120s ended up swapping out STL-10s with the other ones being new locations that didn't replace STL-10s.
+By June 2004, the plant began discussing a system replacement project due to the sirens suffering from advanced corrosion and degrading reliability due to the system's proximity to the ocean. A year later, beginning in November 2005 (a month after the annual siren test), the Model 120s and the STL-10s started to be gradually removed and replaced. By February 2006, all had been replaced by Whelen [[Whelen WPS-2800|WPS-2810]]<nowiki/>s and WPS-2806s that were installed in their places. The 2810s replaced the Model 120s and the 2806s replaced the STL-10s. These new electronic sirens had battery backup and voice capability (that was never used), were much lower maintenance due to their corrosion resistance, and had similar ranges to the sirens they replaced. These new sirens met the strict requirements of the plant without the need to specifically design a new siren. These would be later removed after SONGS was decommissioned. After all the old sirens had been replaced, SONGS sold 23 of the STL-10s to Curry County, Oregon, to be used as tsunami sirens, and the Model 120s and remaining 5 STL-10s were scrapped, save for a single Model 120 that was never installed, kept as a spare for parts and forgotten about. This last remaining unit is currently in private possession by Duderocks5539, undergoing restoration to eventually make it fully operational.
-This was due to the whole siren thing causing delays to the plant by not having a ready siren system by 1981 which was the original year for the plants 2 new reactors that just finished construction, Units #2 and #3 to begin operation, but due to the Sentries originally bought not meeting the plants needs by not effectively covering the EPZ, and the STL-10s still not being good enough, they had to find another siren that meets the plants needs in order for the plants new reactors to start operations which caused a delay for over a year, this also happened around the same time the NRC required Nuclear plants to have siren systems, but until SONGS get sirens that can perfectly cover the 10 mile EPZ, the plants new reactors could not begin operations, and the plants original reactor that was the first reactor to be built in 1968 (Decommissioned in 1992 and completely demolished by 2006) Unit #1 could not be restarted until the siren system is fully operational and effectively covers the EPZ.
+== Design ==
+The Model 120 is a unique mix of a supercharged and pneumatic electromechanical siren that lacks any vanes on the rotor, meaning it requires an external air source to produce any meaningful sound. The sound is created by a 4-port (later 5-port) single-tone rotor, which spins inside the stator and acts as a chamber to contain the air inside. The rotor is driven by a 2 hp TEFC AC motor that runs at 3450 rpm, driving the siren from above. The siren has an 8-port stator, and the sound is then projected by 8 large fiberglass horns attached to the stator. The siren makes use of a belt-driven Paxton centrifugal blower, that uses a 10 hp TEFC motor which sits below the siren's head to force pressurized air up into the rotor. This is a similar configuration to the Japanese [[Hankoku Electric Co., Ltd.|Hankoku]] siren, which also uses a centrifugal blower below the siren.
-So after the Model 120s went up, to end the delays of the siren system not being up to par, which costed over $1 million per day that held up the plant from starting, it was decided to just keep the STL-10s and just add 21 Model 120s in areas that need coverage to get the EPZ effectiveness up to code for the plants original reactor to restart, and the new reactors to start. After a successful system test in July 1983, the plants new reactors began operation shortly afterwards with Unit #2 starting on August 8th, 1983, and Unit #3 on April 1st, 1984, as well as Unit #1 restarted.
+The 4-port units reached a frequency of 240 Hz (480 Hz without the blower due to the lack of air resistance making the rotor spin faster) and the 5-port units reached 300 Hz, or 600 Hz without the blower. The rotor and stator are both coated in Teflon, which helps seal the air in and prevent leaks, while also helping to protect them from corrosion from the salty air. The Model 120 is massive in size, requiring a significant framework to hold up the siren's massive fiberglass horns, as well as the blower and the rotor/stator itself. The siren was designed for being mounted on poles rather than rooftops, attached to the pole either through a custom mount, or reusing the mounts from the Sentry sirens they replaced.
-== Other Information ==
+== Gallery ==
-For around a decade, they were thought to be "Toshiba" sirens, because they were pneumatic and people just assumed they were made by Toshiba, who also made pneumatic sirens. The Model 120 is a Pneumatic siren, meaning it requires an external air source to produce sound. The sound is chopped by a rotor, which sits inside a hollow cylinder, or stator, which acts as a chamber to contain the air inside. 8 Small narrow slots on the stator allow the sound to come out. The sound is then projected by 8 large fiberglass horns. It consists of a belt driven Paxton blower, that uses a 10 Hp TEFC motor. The rotor is 9.75 inches in diameter and has 5 ports. Including the stator it is in total 11.75 inches in diameter. The rotor is powered by a 2 Hp TEFC motor that spins at 3600 RPM.
+<gallery mode="packed" heights="200px">
+Model 120 heads and blowers.jpeg|7 Model 120 heads and blowers prior to being assembled.
-By 6/10/2004, the plant was discussing a system replacement project due to saying the current system is "aging", and a year later starting In November 2005, (a month after the annual siren test), the Model 120s and the STL-10s started to be gradually removed and replaced, and by Febuary 2006 all have been replaced marking October 26th, 2005 as the final test of the original system, as well as the end of the one of a kind original system that stood out from all other Nuclear plant systems. Whelen WPS 2810s and WPS 2806s were installed in their places. The 2810s went in place of the Model 120s and the 2806s went in place of the STL-10s.
+Assembled unit without horns.jpeg|Assembled unit without horns.
+Horns being attached and conduits ran to main junction box.jpeg|Horns being attached and conduits ran to main junction box.
-These new electronic sirens have battery backup, are less maintenance, and having similar ranges to the original system such as the 2806s having better range compared to the STL-10s, and the 2810s having close to the same range but about 2,000 feet less range compared to the the Model 120, but still enough range to cover the EPZ, and as for the strict requirements of the original system, that was no longer an issue as by the 2000s there was commercially produced omnidirectional sirens that have close to the same range as the Model 120 and as well have better range then the STL-10s.
+out of the 8 horns attached with another unit being assembled off to the left.jpeg|5 out of the 8 horns attached with another unit being assembled off to the left.
+Closer view of the head with the siren 95% assembled.jpeg|Closer view of the head with the siren 95% assembled.
-After all the old sirens have been removed and replaced, SONGS sold 23 of the STL-10s to Curry County Oregon to be used as tsunami sirens, and the Model 120s and remaining 5 STL-10s are believed to have been scrapped, but its unknown if they were, or went somewhere else but hasn't been discovered. The only Model 120 that is known and remaining is in the possession of Aaron Allevato (Duderocks5539) and Edaan Friedman and currently under restoration to be brought back into operating condition.[[File:99F6BBFC-E550-4A8C-8538-82E2356B663A.jpeg|thumb|right|upright|Head of the privately owned unit with a motor attached. As you can see it looks exactly the same as the unit in the photo above, just without the horns and frame assembly. The motor is not the exact same motor as the other ones that were installed, but is the same rating, Horsepower, and RPMs.]]
+Fully assembled Model 120.jpeg|Fully assembled Model 120.
+Fully assembled Model 120 with the other 6 being assembled and crated up to be transported to San Onofre Nuclear Generating Station for installation in the 10 mile EPZ around May-June 1983.jpeg|Fully assembled Model 120 with the other 6 being assembled and crated up to be transported to San Onofre Nuclear Generating Station for installation in the 10 mile EPZ in October 1982. These were the first 7 to be installed which replaced 7 STL-10B's.
+IMG 7890.jpeg|Siren Location SC-13 illuminated by a spot light at night in 2003. The siren was 21 years old at the time.
+F6BBFC-E550-4A8C-8538-82E2356B663A.jpeg|Head of the privately owned unit with a salvaged motor attached.
+</gallery>
 == See Also ==
 * Siren patent: https://patents.google.com/patent/US4649853
-* {{Link-inline-video |link=https://www.youtube.com/watch?v=mf7YC0Vc_ZI|name=Model 120 head runup.}}
+* Model 120 head run up: https://www.youtube.com/watch?v=mf7YC0Vc_ZI
-* {{Link-inline-video |link=https://www.youtube.com/watch?v=yOcVk3SrqtY|name=Model 120 head dissasembled.}}
+* Model 120 head dissembled: https://www.youtube.com/watch?v=yOcVk3SrqtY
+[[Category:Sirens]]
-[[Category:SoCal Edison]][[Category:Omnidirectional Sirens]][[Category:Pnuematic Sirens]][[Category:Single Toned Sirens]][[Category:Sirens]]
+[[Category:Omnidirectional Sirens]]
+[[Category:Electromechanical Sirens]]
+[[Category:Supercharged Sirens]][[Category:Single Toned Sirens]][[Category:SoCal Edison]]
+[[Category:Pneumatic Sirens]]
+__INDEX__

Southern California Edison Model 120: Difference between revisions

Latest revision as of 20:49, 19 August 2024

Contents

History

Design

Gallery

See Also

Navigation menu

Southern California Edison Model 120
A Model 120 unit on a Sentry mount.
Company	Southern California Edison
Produced	1982-1988
Type	Supercharged Electromechanical Omnidirectional Pneumatic
Sound output	120 dB @ 100 ft
Horsepower	2 hp (chopper) 10 hp (blower)