https://declassified.library.utoronto.ca/files/original/b2c30fc2c29fc2c7e13f194822fadd1d.pdf ae9ce90acf75e7e7a98fefcc75fdaf32 PDF Text Text Document disclosed under the Access to Information Act Document divulgue en vertu de la Loi sur I'acces a (information U5635 wifilf/ BRITISH EMBASSY WASHINGTON September 25th, 1959. ^^/IcM, ® EMERGENCY POWER SUPPLIES Reference your H.Q.T.S. 1250-36 of September 1 s t . 1. You enquired about our stand-by power resources and arrangements i n the U.K. and I now submit a summary of our f a c i l i t i e s . 2. The Emergency Power arrangements vary somewhat according t o the requirements of our various s t a t i o n s . Overall policy, however, requires t h a t the emergency motors s h a l l be capable of carrying the f u l l operational load, and s h a l l a l s o be capable of being s t a r t e d i n a very short time. & •7 A- %e2_:• .j- • • L«T»C« jk',k The emergency engine i s a 35 k.W. Onan d i e s e l s i t u a t e d i n the ( w W * ^ basement of the building . There i s no cooling-water h e a t e r , but the room $ ~j^My i s kept a t 65°F. The engine i s s t a r t e d by remote control from a push '. button i n the control room, and change-over between engine supply and M> mains supply i s effected by means of a manual change-over switch a l s o v ^••h6^^ situated in the control room. Change-over i n the event of mains f a i l u r e JA"^ takes between 30 and 60 seconds. The engine i s operated a t f u l l load for 30 minutes every Monday morning. &**»• Sbf^ U r 4. Crowborough | ' x iA Crowborough is equipped with a large power station, which is h /(^staffed by diesel engineers at all times. This station generates all the 0/yYP^ y p 0w er consumed by the transmitters on the site and has adequate capacity y^l 'fco ensure a continuous supply. Break-down of supply to a transmitter is very rare (it has happened once in six years) and power can be restored within 2 minutes. However, in order to make the most economic use of engines and to allow regular maintenance, power supply changes take place several times a week. These are always by arrangement with the distant end and, although change-over of the electricity supply is virtually instantaneous, the large transmitters require anything from 2 to 5 minutes to run up to full power. As far as possible, however, the power change-overs are arranged so as not to cut all transmitters simultaneously. 5. C.R.S. The station is equipped with two 27 k.v.a. Lister diesels.. One is started by cranking, but the other is electrically started from a push button in the power house. Electrical change-over is by means of a push button also situated in the power house. The engine is not equipped with a water heater, but the power house is heated. Emergency power is available within 3 minutes of a mains failure. 6. C.T.S. The emergency engine is a 130 k.v.a. diesel, started by compressed air from a manual control in the power station. The engine jacket water is heated, and enables the engine to take full load as soon as it is up to speed. Electrical change-over is done within the transmitting station proper. Power is normally restored within 2 minutes of a mains failure. SECRET 000079 �Document disclosed under the Access to Information Act Document divulgue en vertu de la Loi sur faeces a {'information r *~~e /*•* # SECRET - 2 - 7. The foregoing lists the existing arrangements. These, however, are not the only ones possible and, in new installations, arrangements are to be put in hand that the emergency engine shall start automatically in the event of a mains failure and the change-over between mains and emergency supply shall be by means of a remotely controlled contactor, the control operator being provided with indicator lights and volt-meter so that he can know the state of both the mains and the incoming supply. The engine can be stopped only be means of a push button control and does not stop when the mains is restored. Moreover, over-riding manual controls are provided. This seems to be the best compromise between fully manual control and the fully automatic control, as exemplified in the "no break" type of equipment. This latter equipment consists of a diesel engine alternator and fly wheel. The whole system is normally kept revolving when the mains is available, but on a mains failure the engine begins to fire and supply is available with virtually no break whatsoever. This type of equipment is used where failure of the supply would have disastrous effects or where the equipment is operating unattended and in inaccessible places. It is very expensive and is far more complicated than is justified for any of the services we provide. 8. The yardstick for acceptable delays must, I think, be the times shown above for L.T.C, C.T.S. and Crowborough. This would mean that in the event of a power failure affecting the trans-Atlantic circuit the switch to emergency should not exceed the 30-60 seconds taken by L.T.C. and a failure affecting Hydra should not exceed the 2 to 5 minutes shown for C.T.S. and Crowborough. 9. We are not unduly worried by the absence of an emergency supply for the 100 KW at Oshawa as the Hydra circuit could still be maintained satisfactorily for the period of failure on Oshawa*s two other smaller transmitters. M/C fa^ /-<y) £*'< ^jpus^? %s*y Lt.-Col. W.E. Grant, Royal Canadian Corps of Signals, Department of N a t i o n a l Defence (Army), OTTAWA. IPECRET 000080 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Hydra Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Identifier An unambiguous reference to the resource within a given context HY00082 Title A name given to the resource Emergency Power Supplies Date A point or period of time associated with an event in the lifecycle of the resource 09/25/1959 Source A related resource from which the described resource is derived Hydra Communications - Policy, RG24, 1250-36 Vol. 1, Library and Archives Canada (LAC) Creator An entity primarily responsible for making the resource Department of National Defence Rights Information about rights held in and over the resource Canadian Crown Subject The topic of the resource DND, British Embassy, Washington, LTC, OWS, emergency communications Description An account of the resource Letter from Mathews (Attache, British Embassy, Washington) to W.E. Grant (D Sigs) pertaining to emergency power supplies at radio transmitting/receiving facilities in the UK. British officials are not "unduly worried" about Oshawa's lack of power backup, as Hydra circuit could be maintained on Oshawa's two smaller transmitters. Publisher An entity responsible for making the resource available Canada Declassified Type The nature or genre of the resource Text Format The file format, physical medium, or dimensions of the resource PDF Language A language of the resource en