Southern California Edison Model 120: Difference between revisions

	Southern California Edison Model 120
	; Installed unit on a Wood pole.
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 03:54, 27 October 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 October 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.

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 on May 4th, 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, 8 of which were installed, 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, 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.

Originally, the rotors were 4-port, and reached a frequency of 240 Hz (480 Hz without the blower due to the lack of air resistance making the rotor spin faster) But later changed to 5-port due to issue of standing waves, which reached 300 Hz, or 600 Hz without the blower. (The last remaining unit never received a 5-port rotor due to not being installed.) 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.

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.

Footnotes

↑ While Southern California Edison Model 120s were once referred to as "Toshiba" sirens by enthusiasts when they were still being speculated, these were not made by Toshiba. These were purely a custom-made design built in-house by Southern California Edison.

[1] While Southern California Edison Model 120s were once referred to as "Toshiba" sirens by enthusiasts when they were still being speculated, these were not made by Toshiba. These were purely a custom-made design built in-house by Southern California Edison.

[1]

@@ 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=Installed unit on a Wood pole.|hp=2 hp (chopper)
-}}
+hp (blower)}}
-The SoCal Edison (SCE) 120 or Model 120 was a SoCal Edison manufactured 120 dB siren which was designed by John Glenn Powell. He is a now retired worker that worked at the San Onofre Nuclear Generating Station located in San Clemente, California and was also a sound engineer. 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 33 Federal Signal STL-10s that were installed in April 1982 with 2 of the STL-10s being swapped out for Model 120s, and later in 1988 4 additional locations were installed one of which replacing a Thunderbolt that was actually a CD siren used by one of the cities before SONGS took over it for use in their siren system. The reason these sirens were made is because there was no other siren available that would meet the plants needs. 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. They did look into ACA Cyclones which was the most powerful omnidirectional siren available, but they realized it didn't have the coverage the plant wanted being about 3,000 or so feet less the then plants range requirement, and the fact that they have massive 50 Hp motors which was overkill for a siren with such a range of only about 4,000ish feet. The other reason is because the STL-10s underperformed in all areas they were placed in, as well as federal lying to SoCal Edison about the STL-10 being 120 decibels and having the specific effective range that the plant required (which was about 6,000 or more feet effective range) to cover the EPZ due to the hilly terrain of the jurdisctions in the EPZ.
+The '''Southern California Edison Model 120'''<ref>While Southern California Edison Model 120s were once referred to as "Toshiba" sirens by enthusiasts when they were still being speculated, 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.
-So starting in around June 1982, Model 120 prototypes started to be constructed and tested, with the final designed units being completed in March 1983, and the first 16 installed in July 1983, and later on 4 more in 1988 to cover new housing and business development in a part of the city of San Clemente that was being constructed around 1987 bringing the total to 21 Model 120s and a total number of 52 sirens with the already existing 32 STL-10s.
+== History ==
-Originally the plan was after the Model 120s installed, a now total of 50 sirens were going to be all Model 120s which means swapping out the existing 32 STL-10s with 120s making the system 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. 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 STL-10s originally bought not meeting the plants needs by not effectively covering the EPZ, 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. So after the Model 120s went up, to end the delays and costly over 1 million per day it takes to get the siren system ready and stop holding up the plant from starting, it was decided to just keep the underperforming 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 October of 1982, the plants 2 new reactors began operation a few months later in early 1983.
-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. 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. These new electronic sirens have battery backup, are more efficient, 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. 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:Model 120 prototype being mounted to an existing STL-10 pole for range and output testing in 1982.jpeg|thumb|left|Model 120 prototype being mounted to an existing [[Federal Signal STL-10|STL-10]] pole for range and output testing in Summer 1982.|160x160px]]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 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 October 1982.
-Siren patent: https://patents.google.com/patent/US4649853
+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 on May 4th, 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 [[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, 8 of which were installed, 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, 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.
-[[File:3D5E51FE-62BF-4D63-B5E6-2733B5E18F00.jpeg|thumbnail|The Paxton centrifugal blower w/o motor (rear view showing the two belts and pulleys without the cover on.)]]
+== 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.
-[[File:DD45D32B-46D1-48B1-A15C-ADA5FEC67066.jpeg|thumbnail|The blower w/o motor (rear view with the cover on.)]]
+Originally, the rotors were 4-port, and reached a frequency of 240 Hz (480 Hz without the blower due to the lack of air resistance making the rotor spin faster) But later changed to 5-port due to issue of standing waves, which reached 300 Hz, or 600 Hz without the blower. '''(The last remaining unit never received a 5-port rotor due to not being installed.)''' 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.
-[[File:0EFDB333-123B-4FC0-AF14-868231AE3019.jpeg|thumbnail|The front of the blower showing the intake and motor mount. It uses a 10 Hp 1 phase motor.]]
+== Gallery ==
-[[File:05DD7AB0-BB48-485E-BDD3-A023264A72B0.jpeg|thumbnail|Looking down the blower intake showing the impeller, which has a really tight tolerance and in conjunction with the rotors very high tolerance. They both work excellently and eliminate the need for a large heavy roots blower.]]
+<gallery heights="200">
+File:7 Model 120 heads and blowers.jpeg|7 Model 120 heads and blowers prior to being assembled.
+File:Assembled unit without horns.jpeg|Assembled unit without horns.
+File:Horns being attached and conduits ran to main junction box.jpeg|Horns being attached and conduits ran to main junction box.
+File:5 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.
+File:Closer view of the head with the siren 95% assembled.jpeg|Closer view of the head with the siren 95% assembled.
+File:Fully assembled Model 120.jpeg|Fully assembled Model 120.
+File: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.
+File: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.
+File:99F6BBFC-E550-4A8C-8538-82E2356B663A.jpeg|Head of the privately owned unit with a salvaged motor attached.
+</gallery>
-[[File:0DDD1D27-DFDB-447F-A6B8-807F1C5A38D9.jpeg|thumbnail|A Model 120 (SONGS Siren Location SC-13) In 2003, before being replaced by a Whelen WPS 2810 2 years later.]]
+== See also ==
-[[File:CA38B627-CA13-4A5D-8099-24B6CE254123.jpeg|thumbnail|Top of the head of a unit in a test chamber showing the top of the horns, the rotor and stator, and rotor motor.]]
+* Siren patent: https://patents.google.com/patent/US4649853
+* Model 120 head run up: https://www.youtube.com/watch?v=mf7YC0Vc_ZI
+* Model 120 head dissembled: https://www.youtube.com/watch?v=yOcVk3SrqtY
-[[File:99F6BBFC-E550-4A8C-8538-82E2356B663A.jpeg|thumbnail|rotor and stator 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.]]
+== Footnotes ==
+[[Category:Sirens]]
-[[File:Installed unit on wood pole overlooking trees.jpeg|thumbnail|Just installed unit on wood pole overlooking trees.]]
+[[Category:Omnidirectional Sirens]]
+[[Category:Electromechanical Sirens]]
-[[File:Another unit on wood pole over looking trees.jpeg|thumbnail|Another just installed unit on wood pole over looking trees.]]
+[[Category:Supercharged Sirens]][[Category:Single Toned Sirens]][[Category:SoCal Edison]]
+[[Category:Pneumatic Sirens]]
-[[File:Unit on a steel pole looking upward from ground view.jpeg|thumbnail|Just installed unit on a steel pole looking upward from ground view.]]
+__INDEX__
-[[File:Timer.jpeg|thumbnail|Signal Timer and enclosure.]]
-[[File:Radio-decoder.jpeg|thumbnail|Radio/decoder and enclosure.]]
-[[File:Service-manaul power switches.jpeg|thumbnail|Breaker panel switches.]]
-[[File:Model 120 installation blue print.jpeg|thumbnail|Installation blueprint for a steel pole installation.]]
-[[Category:SoCal Edison]][[Category:Omnidirectional Sirens]][[Category:Pnuematic Sirens]][[Category:Single Toned Sirens]][[Category:Sirens]]

Southern California Edison Model 120: Difference between revisions

Latest revision as of 03:54, 27 October 2024

Contents

History

Design

Gallery

See also

Footnotes

Navigation menu

Southern California Edison Model 120
Installed unit on a Wood pole.
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)