Jon,
Of course 16 amps for an entire apartment is way too little. But a 16 amp branch circuit at 230V single Phase is going to handle a continuous load of 3,600 Watts...
A lot of these outlets and installations are very old and no longer code. Generally speaking, 230V installations make possible much thinner wires, the plugs are really quite stable.
It's the old problem, double the voltage, halve the current, cut the heat 75%.
Single phase, split-phase, two-phase, three-phase have all lead to some really nasty discussions here so I strongly urge the anal-retentive to resist the urge to attack. This stuff is interesting, let's not turn it into the dog fight the last two discussions were...
Split-phase, to answer the question, is a simple answer to the difficult problem of how to satisfy heavy consumers - cooker, dryer, water heater while still serving normal consumers - stereo, TV, lighting, refrigerator, etc.
As I noted above, when you double voltage you reduce the current by half. That means you can reduce the conductor size in the wiring considerable - not quite proportionally because of physical limits, but enough that the savings on copper and weight are considerable. It is the current which generates heat, not voltage.
To get split phase, all you need to do is to take a single phase AC input. It can be of higher or lower or the same voltage, but is often considerably higher. This input goes to the primary taps of a transformer. The secondary taps of the transformer have an extra, center tap. Between the two outside taps you have (for instance) 240 Volts. Between either of the outside taps and the center tap you have 120 volts. All you have to do is run that center tap (Neutral) and the two outside taps to the service panel and all sorts of problems are resolved. With careful load balancing, it should be possible to even run duplex 120V outlets with only one neutral but each socket having one of the split phases (obviously you'd want to pigtail those, not to think what would happen if the first outlet of a branch series were simply removed and that neutral disconnected).
Non-anal-retentives call this "two-phase", tho', of course it isn't.
I'd rather have three phase any day, but the solution is admirably simple, reliable and proved.
Some parts of the UK use a "ring" system which, when properly done, saves copper and provides a more consistent voltage. Be nice to hear about that.

Of course 16 amps for an entire apartment is way too little. But a 16 amp branch circuit at 230V single Phase is going to handle a continuous load of 3,600 Watts...
A lot of these outlets and installations are very old and no longer code. Generally speaking, 230V installations make possible much thinner wires, the plugs are really quite stable.
It's the old problem, double the voltage, halve the current, cut the heat 75%.
Single phase, split-phase, two-phase, three-phase have all lead to some really nasty discussions here so I strongly urge the anal-retentive to resist the urge to attack. This stuff is interesting, let's not turn it into the dog fight the last two discussions were...
Split-phase, to answer the question, is a simple answer to the difficult problem of how to satisfy heavy consumers - cooker, dryer, water heater while still serving normal consumers - stereo, TV, lighting, refrigerator, etc.
As I noted above, when you double voltage you reduce the current by half. That means you can reduce the conductor size in the wiring considerable - not quite proportionally because of physical limits, but enough that the savings on copper and weight are considerable. It is the current which generates heat, not voltage.
To get split phase, all you need to do is to take a single phase AC input. It can be of higher or lower or the same voltage, but is often considerably higher. This input goes to the primary taps of a transformer. The secondary taps of the transformer have an extra, center tap. Between the two outside taps you have (for instance) 240 Volts. Between either of the outside taps and the center tap you have 120 volts. All you have to do is run that center tap (Neutral) and the two outside taps to the service panel and all sorts of problems are resolved. With careful load balancing, it should be possible to even run duplex 120V outlets with only one neutral but each socket having one of the split phases (obviously you'd want to pigtail those, not to think what would happen if the first outlet of a branch series were simply removed and that neutral disconnected).
Non-anal-retentives call this "two-phase", tho', of course it isn't.
I'd rather have three phase any day, but the solution is admirably simple, reliable and proved.
Some parts of the UK use a "ring" system which, when properly done, saves copper and provides a more consistent voltage. Be nice to hear about that.
