PS-CT: ERD-2 switch tank harmonization T. Kramer 02/10/2017 TCM

Today NSG ERD-2 Current ERD-1 02/10/2017 TCM

Today In operation: 5 NSG switch tanks (double branch), 20 PFL ) 1 ERD-1 switch tank (NSG type, only single branch used, 2 PFL) Space and cooling water outlets already foreseen for 5 tanks. 6 spare switch tanks (NSG type) available (3 tested) 02/10/2017 TCM

Move to NSG type Supress RSG type IDEA: Move RSG(ERD-2) system to NSG type switch tank ( hence use 4 of the todays 6 spare tanks in single branch mode) Move to NSG type Supress RSG type Advantages: Advantages: All switch tanks available ( 8 tested, 4 to be tested), tank infrastructure ready except cables. Tank smaller and on wheels – easier maintenance and exchange (in the future 1 redundant branch, hence no tank exchange if thyratron fails, simply plug 4 power cables to 2nd branch) Significantly reduced oil volume (2800ltr less) Suppress one generator type, Supress one thyratron type (1191D, only place used) + faraday cage Supress one step up transformer type Reduce oil quantity significantly (2800ltr, no retention pan yet, pain to install) Significantly Reduce RG220 quantity in Building 359 (PVC jacket?) Current build-in redundancy of RSG tank difficult to use (change of generator side/never exercised, whilst it would be really available with the NSG type tank) Mid-term free significant Volume in B.359 Disadvantages: New controls and supply cables to be pulled (but some RSG cables would anyway need replacement e.g. for thyratron heater, power supply cables are very old etc.) ? 02/10/2017 TCM

Cables Present biggest possible work load and overhead if completely renewed. Future ERD-1 and ERD-2 would anyway need new heater supply cables (new “ branch selection crate” available but old cables don’t support this functionality). “ Some” new controls cables already pulled but not yet connected. Decabling of “some” old cables foreseen for YETS. Relatively short cables with good routing/accessibility. Tx cable length to be checked (seems to have quite some reserve below false floor, but exact length needed. Need to verify exact cable status in case of “go-ahead” and update/modify decabling request. 02/10/2017 TCM

Cooling Space foreseen Connections for cooling already installed 02/10/2017 TCM

Cable trays there (space?) Power cables installed (tested?) Some controls cables installed but marked for decabling (too old?) Cable identification possibly the most complex/time consuming task. 02/10/2017 TCM

Proposed Schedule Decision go-ahead/stop: Beginning of October 2017 If green light: Detailed planning: October 2017 DIC (as needed): November 2017 (deadline EOY) Adjustment of YETS decabeling scope (if necessary): November 2017 Integration into Spec./ECR: Q4/2017 Check of spare switch tanks: during operation until EOY2017 Test of switch tanks: YETS (recommissioning period) Power cabling check/connection: YETS (profit from decabling) All other work: LS2 02/10/2017 TCM

Resources Estimate PPE/KSC EC Extern EN-EL: Worst case: Likely: Engineer: 2 week updating documentation, preparing requests etc. follow up of execution. 1 day for spare tank testing 2 days commissioning Technician: 1 day (technician) for: spare tank check and test power connections FSU: 2 days preparing hydraulic connections (hoses), exchanging cable reels, preparation of chariot and displacement of end diode/resistor and switch tanks. Technical Engineer 1 week for preparation work, update of documentation, DIC 1 week for execution( e.g. reconfigure AFO, KiTS etc.) 2 days EN-EL/FSU help/supervision 2 days commissioning FSU 1 week connectors installation, reconnection of system (Assuming that EN-EL is doing the cabling (would be possible within ABT (FSU) as well) EN-EL: Worst case: Installation of 56 max. 30m long cables. Ev. more cable trays if needed. Likely: ~ 40 new controls cables on existing cable trays. Total: Eng.: 2.5 weeks Tech. Eng.: 2.5 weeks Tech. 2 d FSU. 10 d + EN-EL Dismantling of RSG not included (stays as spare for transition period). How much can be absorbed in standard operations/ maintenance activities and by the CT reconfiguration? 02/10/2017 TCM

Conclusions Change over of ERD-2 from existing RSG type tank to NSG type tank and current ERD-1 location is carries benefits and is reasonably feasible. Significant reduction of oil and cable volume once RSG completely removed. Suppression of one unique generator type (and thyratron), easier maintenance on ground floor, 2nd branch with “real” switch over capability Resources needed could be partly absorbed by operational budget and PS-CT reconfiguration (uncertainty until detailed planning established: scope of cabling). 1st Estimates (maximum): HR: 6 weeks staff, 2 weeks FSU Cost: cabling and FSU cost (rough guestimate 15k?). 02/10/2017 TCM