Sandwich maker amperage
The current when it is heating will be about 3A. There may be a thermostat that cuts it off before it overheats (thus maintaining a reasonable cooking temperature), but when it is heating the current will be about 3A with the nominal 230V line voltage. 

The resistivity of the (probably) Nichrome (80% Nickel- 20% Chromium alloy) heater windings is much, much higher than copper or aluminum, and they are long and thin rather than thick, which is why the wires in the line cord do not get noticeably warm, but the sandwich maker surfaces get too hot to touch.