22 gauge tinned stranded 600v wire for heaters ?

[nsubulysses]

I'm curious why people don't like stranded? Solid core is annoying to me because it breaks easily when bent. Maybe I've had too much bad experience with V4s

[Raybob]

Can't say I don't 'like' it, but same size wire solid core handles more current than stranded. 22 ga solid core works for heaters without getting hot. Can't say same thing about 22ga stranded, never having tried that.

[catalin gramada]

It is a reason "hook up" wires are called for. You cannot make a hook with stranded one.

[Gingertube]

Wire has a continuous current rating in free air at a particular ambient temperature.
The rating is based entirely upon the temperature rise in the wire + the ambient being below the temperature rating of the wire.

That current rating gets reduced when wires are bundled together (as in 2 wires "bundled" for a heater wiring run) since there can be mutual heating from adjacent wires.
That current get reduced again for higher ambient temperature (less temp rise in wire can be tolerated and still stay below max wire temp)
Also gets reduced again for high altitude (e.g. use in aircraft) or if you live in Denver or some place high up. (Denver guys don't freak, the derating factor for you guys is like 0.95).

Use this table
Wire Gauges - Current Ratings
Take the current values from the up to 3 cores (means 3 wires bundled) column.
It gives you conservative and therefore safe values (typical values of all those de-ratings mentioned have already been applied).
Note that it tells you 3 Amps max. for 22 AWG heater run.

I typically run 16 AWG to power tubes and 20 or 22 AWG to preamp tubes.

I also do aircraft equipment design where we have to do all those calcs. for each wire and prove that there is a fuse or circuit breaker of lower than the wire current rating in the feed to that circuit - to get CASA (Aussie version of FAA) design approval.

Cheers,
Ian

[danman]

This 22awg Topcoat wire is my favorite in my Marshall style builds. It is pretinned for easy soldering, holds it shape great and the insulation holds up great to soldering heat...http://valvestorm.com/Products/Wire