After a 3 a.m. fault locate on a 15 kV JCN primary, I’m trying to pin down when water‑swellable conductors/neutrals became the default in your territories — was it mid‑90s, 2000s, or later? I’m cross‑checking failure logs because longitudinal wicking under the jacket keeps showing up on older dry-core runs, and dialing our spec will cut repeat dig‑ups.
In our Midwest IOU, water‑swellable neutrals went spec around 2004 and full water‑blocked cores by 2007; most wicking headaches show up on pre‑’04 dry‑core. Quick check: look for “WS” or “WTRBLK” on the print and old POs from 2003–2006, @OP — what utility/region are you mapping? Anything older tends to drink like a sponge.
PNW muni here: neutrals went water‑swellable about 2002 and full water‑blocked TR‑XLPE URD became default by 2006; our problem children are the pre‑’02 JCN runs. Quick field tell: look for jacket print like “WS”/“WB,” or crack a cutback — if you see dry swell tape under the concentric instead of peanut‑butter flood, it’s the newer spec. What region and who supplied your older lots — Southwire, Okonite, Kerite?