Does Siemens original flowmeter have a certificate of approval?

I don't think so. Generally, there is no so-called certificate for imported instruments. This thing is played by China people themselves. The concept of foreigners is that the products you can buy should be qualified, and the unqualified products cannot be sold to you. But it will be troublesome to check and test in China. As long as it's clear, it's easy to say that if you meet a car owner who doesn't understand, you'll be in trouble. Just ask you for a proof. Where are you going?