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BIRNS SIZE “P38” Penetrator has 1.5-12-UN-2A mounting threads, and is available with up to 56 conductors. The standard configuration includes 3m (10′) of neoprene-jacketed cable inboard and outboard; other cable lengths and materials are available. The outboard cable may be 90º or 180º. Specify other conductor sizes, stem lengths, configurations, and/or materials.

To mount the P38100 penetrator, insert the penetrator into its mounting hole in the bulkhead, and install the first jam-nut until it is against the bulkhead. While holding the penetrator in place, achieve 12-16 in-lbs of torque on the first jam-nut against the bulkhead. Then assemble the second jam-nut on top of the first jam nut and torque it to 25-30 in-lbs while holding the first jam nut stationary.

This may be difficult to do because jam nuts have a short height and a thin wrench or a crow’s foot may be required in order to hold the first nut against the bulkhead. If you have sufficient available space, the same effect can also be achieved with two full nuts—or a full nut and jam nut, which would make holding one nut while torquing the other easier. The same procedure is used above where the first nut has the lower torque value.

P19 (.75-16) UNF -2A P25 (1.0-14) UNS-2A P32 (1.25-12) UNF -2A P38 (1.50-12) UNF -2A BIRNS UTS (UN) penetrators are constructed of AISI 316 stainless steel, passivated per QQ-P-35 type VI.  All cables are mechanically reinforced with high strength potting compound and seal-overmolded with polyurethane. BIRNS UTS (UN) penetrators meet or exceed ABS and DNV requirements when fabricated with Low Smoke Zero Halogen (LSZH) cables inboard.  All BIRNS penetrators are individually serialized, certified and tested in accordance with BIRNS’ ABS-approved test procedure ETP-6510-101.


BIRNS can customize penetrators to specific requirements, including:
  • Cable length (inboard and outboard)
  • Conductor quantity and size
  • Straight or 90° cable molding
  • Cable jacket material
  • Test methods and witnessing

Specific Customizations:

  • Cable Length (inboard to 18m/60′; outboard to 3m/10′ or on special order to 4.5m/15′)
  • Cable Stock, including conductors quantity and size (See conductor color coding)
  • Wiring of TSP/STP (screened twisted pairs):
    • leave the shields not connected (“floating shields”)
    • “marry” all (or some) of the shields to one or more or more penetrator pins
    • terminate each shield to its own penetrator pin
    • terminate overall shield to Penetrator shell…or isolate it from the shell, as you prefer
  • Straight or 90° cable molding
  • Cable jacket material. We use BIRNS 52D-089 LSZH wire (tails/flying leads) inboard unless otherwise specified. For 52D-089 LSZH wire inboard, add the suffix “-LS” to the part number (e.g. P38100-24-RA-LS)
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