TTY

What is TTY cable?

TTY: shipboard paired telephone and instrumentation cable, 150/250 V, PVC sheath. Rating: 150/250 V AC, 225/375 V DC; conductor 70 °C (PVC insulation); 0.75 mm² conductors, 1 to 48 pairs (Table 25 Notes 1 and 2, p. 41). Standard: JIS C 3410:2010 Table 1 (p. 5) and Table 25 (p. 41); built on IEC 60092-351, -353, -354, -359 and -376 (Introduction, degree MOD).

Read in JIS C 3410:2010 (JSA English translation), seen: standard. Table 25 (p. 41): 1 to 48 pairs (also one triple 1T and one quad 1Q) of 0.75 mm² plain annealed copper (7/0.37 mm); PVC insulation 0.6 mm, white, one core of each pair numbered (6.10.2); pairs twisted at a pitch of at most 120 mm (6.11.1); PVC sheath 1.0 to 2.3 mm; steel braid wire 0.3 mm (0.4 mm from 24 pairs); PVC protective covering 0.8 to 1.7 mm; routine test 1 500 V. Galvanised steel braid wire 0.3 or 0.4 mm (5.11.1, Table 7, p. 19), one over one under or two over two under, coverage at least 90 % (F at least 0.573, 6.16, p. 23); braid paint and protective covering white at 150/250 V and 0.6/1 kV, red at 3.6/6 and 6/10 kV, grey for fire resistant cables (6.16 c, 6.17, p. 24). Designation (cl. 10, p. 29): the symbol, a hyphen and the conductor size in mm², for multicore cables the number of cores, for telephone cables the number of pairs ("0.6/1 kV SPYC-120", "150/250 V MPYCY-12", "150/250 V TTYC-10"). FA- (flame retardant, bunched test 7.7: char at most 2.5 m) and FR- (fire resistant, mica tape under the insulation, 6.3, IEC 60331-21 or -31, 7.8) prefix the symbol. TMC prints the same name in its catalogue (manufacturer).

Documents and pages the readings were taken from

• JIS C 3410:2010, JSA English translation (first English edition 2011-09): Table 1 types and symbols pp. 2 to 8, Tables 2 and 3 letters pp. 8 to 9, construction Table 25 (p. 41)
• powerandcables.com

JIS C 3410 shipboard cables: how to read the cable type names