rhaynes
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The max peak current rating of the diode which is the spec you need to look at is 400mA for the 1N4148. The relay coil current is ~180mA which is also the current you'll get with the back EMF when the driver opens so a 1N4148 will be fine. But the relay release time will increase which could be a problem and that can be helped by using a 4V zener in series with the diode to allow the back EMF voltage rise up to about 5V.
Also a while back you asked about hot vs neutral switching. Here in the U.S. we have 2 types of 2 prong plugs, one polarized and one not. If a non-polarized plug is used then you have no idea which is wire is hot which is usually not a problem. If it is a concern then a polarized 2 prong plug or a 3 prong grounded plug, which end up also being polarized, could be use. No matter what type of plug you use you are still relying on the electrician to have wired the outlet correctly. So bottom line for safety is to consider both sides as possible hots.
Ray
Also a while back you asked about hot vs neutral switching. Here in the U.S. we have 2 types of 2 prong plugs, one polarized and one not. If a non-polarized plug is used then you have no idea which is wire is hot which is usually not a problem. If it is a concern then a polarized 2 prong plug or a 3 prong grounded plug, which end up also being polarized, could be use. No matter what type of plug you use you are still relying on the electrician to have wired the outlet correctly. So bottom line for safety is to consider both sides as possible hots.
Ray
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