I purchased from Lazada an Aukey Underwater Pool Pond Light (white). It comes with about a 3cm 2-wire lead.

But when I attempt to test the light by adding a plug-in it instantly trips the electric circuit protected with a bitcino BTP1C16 240/415V.

I replaced the breaker with a BTP1C20 and it still trips.

What am I missing or is the light unit defective?

It's a 12V light.

It's probably dead now

I would say so, since the description describes it as a 12V device.

is your step down transformer faulty or not set at right voltage that you are plugging in

Just for added info I went to the Lazada site and 3 lights I saw clearly say 12V spec. No stepdown transformer in packages just the light.

So it needs a stepdown low voltage transformer?

What might I look for in Lazada for example?

Something like this http://www.lazada.co.th/led-smd-light-tube-strip-mr16-mr11-bulb-driver-transformer-power-dc-12v-intl-3496687.html would drive one of the lamps in the OP.

Our OP will also need a new lamp, there is no doubt whatever that if it's been connected to the 220V mains it is history.

Something like this http://www.lazada.co.th/led-smd-light-tube-strip-mr16-mr11-bulb-driver-transformer-power-dc-12v-intl-3496687.html would drive one of the lamps in the OP.

Our OP will also need a new lamp, there is no doubt whatever that if it's been connected to the 220V mains it is history.

Thanks for everyone's help.

Obviously not something a layperson should buy and the ad should have mentioned transformer required for operation. Between buying a new bulb and transformer I might as well buy a new unit with built-in transformer.

Something like this http://www.lazada.co.th/led-smd-light-tube-strip-mr16-mr11-bulb-driver-transformer-power-dc-12v-intl-3496687.html would drive one of the lamps in the OP.

Our OP will also need a new lamp, there is no doubt whatever that if it's been connected to the 220V mains it is history.

Thanks for everyone's help.

Obviously not something a layperson should buy and the ad should have mentioned transformer required for operation. Between buying a new bulb and transformer I might as well buy a new unit with built-in transformer.

While you can try a new bulb in that unit, I think Crossy is seriously recommending you throw that unit out as the damage caused by having ~220v run though it makes its future safety highly questionable.

The fact that it's currently providing a dead short doesn't bode well for the condition of the wiring.

Something like this http://www.lazada.co.th/led-smd-light-tube-strip-mr16-mr11-bulb-driver-transformer-power-dc-12v-intl-3496687.html would drive one of the lamps in the OP.

Our OP will also need a new lamp, there is no doubt whatever that if it's been connected to the 220V mains it is history.

Thanks for everyone's help.

Obviously not something a layperson should buy and the ad should have mentioned transformer required for operation. Between buying a new bulb and transformer I might as well buy a new unit with built-in transformer.

Actually, for safety I would not recommend a unit with a built-in transformer, these things are low-voltage for a reason.

Keeping (lethal) mains away from your pond / pool should be a number one priority.

Replace the fried unit, buy a transformer to go with it, be safe.

Crossy speaks very true. That's a principal reason why yachts will invariably have 12V or 24V wiring throughout. Some of the superyachts will have 110-220 but still not a good idea.

On a positive note your circuit protection worked.