DDG-51 DDG-51
DDG 51 CLASS ADVISORY NR 02-93
AN-SPY-1D HIGH VOLTAGE POWER SUPPLY POTENTIAL SAFETY HAZARD
REF/A/DOC/NAVSEA/-//
REF/B/DOC/NAVSEA/-//
REF/C/DOC/NAVSEA/-//
NARR/REF A IS TECHNICAL MANUAL, NAVSEA SW279-CR-AEG-090/OT-
146/SPY-1D. REF B IS MRC 4560/R07-92. REF C IS NAVSEA S9AAO-AB-
GOS-010, GEN SPECS FOR OVERHAUL OF SURFACE SHIPS, SECTION 602H.//
RMKS/1. THIS ADVISORY IS INTENDED TO ALERT ALL PERSONNEL
INVOLVED WITH THE OPERATION AND MAINTENANCE OF SUBJECT EQUIPMENT
TO A POTENTIAL SAFETY HAZARD WITH THE NEW HIGH VOLTAGE POWER
SUPPLY INTERLOCKS IN THE AN/SPY-1D SYSTEMS. THIS ADVISORY
APPLIES TO DDG 51 AND FOLLOW.
2. BACKGROUND. THE RIGHT BARRIER SCREEN AND CABLE ENTRY PANEL
HAVE CHEATABLE INTERLOCKS WHICH, IF BYPASSED, ALLOW HIGH VOLTAGE
TO EXIST WITHIN THE POWER SUPPLY. THIS PROBLEM WILL BE CORRECTED
BY THE INSTALLATION OF ORDALT (O/A) 20213, WHICH WILL REPLACE THE
CHEATABLE INTERLOCK WITH A NON-CHEATABLE INTERLOCK. ANTICIPATE
THIS O/A WILL BE AVAILABLE BY JUNE 1994.
3. ACTION.
A. PRIOR TO PERFORMING MAINTENANCE ON THE HIGH VOLTAGE
POWER SUPPLY IAW REFS A AND B, ENSURE THAT THE FOLLOWING STEPS
HAVE BEEN TAKEN:
(1) THE GROUNDING ROD IS CONNECTED TO THE "GROUND
HERE" POINT AT ALL TIMES WHEN THE BARRIER SCREEN DOOR IS OPEN.
(2) HIGH VOLTAGE POWER SUPPLIES ARE IN LOCAL CONTROL
BEFORE OPENING THE CABLE ENTRY PANEL.
(3) DISCHARGE AND GROUND ALL HIGH VOLTAGE CAPACITORS
AND EXPOSED HIGH VOLTAGE TERMINALS. PERFORM THIS STEP SEVERAL
TIMES TO ASSURE THAT ALL HIGH VOLTAGE TERMINATIONS HAVE BEEN
COMPLETELY DISCHARGED.
(4) DO NOT BYPASS THE BARRIER SCREEN DOOR INTERLOCK
(S7) OR THE CABLE ENTRY PANEL INTERLOCK (S6) IN THE HIGH VOLTAGE
POWER SUPPLY.
B. ON THE FRONT PANEL OF EACH POWER SUPPLY INSTALL A
WARNING SIGN FABRICATED IAW REF C READING AS FOLLOWS:
WARNING
HIGH VOLTAGE - DO NOT BYPASS BARRIER
INTERLOCK S-7 OR PANEL INTERLOCK S-6
4. FOR COMNAVSURFLANT - REQUEST DDG 51 AND DDG 52 BE TASKED TO
ADHERE TO THE ABOVE SAFETY PRECAUTIONS.
5. FOR SUPSHIP PASCAGOULA/BATH - REQUEST SHIPYARD PERSONNEL AND
DDG 53 AND FOLLOW SHIP PRECOMUNITS BE NOTIFIED TO ADHERE TO THE
ABOVE SAFETY PRECAUTIONS.
6. FOR NSWC PHD - SINCE ORDALT 20213 IS NOT IMMEDIATELY
AVAILABLE, INCORPORATE THE FOLLOWING SAFETY PRECAUTION INTO
APPLICABLE MRC'S (Q-8, Q-17, 18M-4, AND 60M-10) OF REF B PMS -
"DO NOT BYPASS BARRIER INTERLOCK S-7 OR PANEL INTERLOCK S-6".
7. THIS ADVISORY HAS NO IMPACT ON EOSS, CMMP OR TECHNICAL
DOCUMENTATION. IT WILL BE CANCELLED UPON COMPLETION OF ORDALT
20213 IN ALL APPLICABLE SHIPS.
8. POC IS MR N. S. SMITHSON, PMS400F511, DSN: 332-5981 OR COMM
(703) 602-5981. NSWC PHD TECHNICAL POC IS MR J. CHUNG, CODE
4C11, DSN: 551-8689 OR COMM (805) 982-8689.//