Hello Paul,
Thank you for writing in.
Could you please tell us more details of your application, such as the type of the automotive tachometer signal?
Where are you going to use this product?
With your help, we can find a solution more quickly.
Best regards

Hello Rob,
Thank you for your reply.
As your description, this product may be defective.
We have tested our products before shipping to Amazon warehouse.
This problem may be caused by the shock during delivery but it is hard for us to ensure the exact cause without the product.
So sorry for the trouble caused on you and all we want to do is to try our best to find a solution to you.
Could you please tell us your order ID so that we can contact you via Amazon?
Beg your forgiveness and waiting for your reply.
Best regards

Hello jason martin,
Thank you for writing in.
So sorry that we cannot provide the Rohs certification for you right now.
The Rohs certification is on the way.
We are still trying our best to apply the certification, but this process is a little complicate and we need time to make it.
Beg your understanding.
Best regards

Hello Austin,
Thank you for your reply.
We have contacted via Amazon, please check it.
Best regards

Hello Rob,
Thank you for your reply.
It is better that you can tell us more details of your operation, such as the input voltage/current, the load, the wiring, the working environment.
If you can, we sincerely hope that you can send us some images of your wiring to let us check the problem details.
You can send this information to us by email (service at droking dot com).
With your help, we can find a solution more quickly.
Looking forward to hearing from you.
Best regards

Hello Michael,
Thank you for writing in.
Could you please tell us more details of your operation, such as the load, the wiring, the working environment?
If you can, we sincerely hope that you can send us some images of your wiring to let us check the problem details.
You can send this information to us by email (service at droking dot com)
Looking forward to hearing from you.
Best regards

Hello LT4,
Thank you for your reply.
All the meters, which the measured current range is over 10A, need to use with a shunt, otherwise, the meter will be burnt.
This 100A meter must be used with a shunt but so sorry that there is not a shunt included in the package.
Beg your understanding.
Besides, is the current range of your fan 0-1.2A?
If yes, this meter may be not suitable for your application.
It is recommended that the measured current range of the meter is twice as the real measured current.
If the measured current range is too wide , it will affect the accuracy.
Hope this can help you.
Best regards

Hello kevin wallcroft,
Thank you for writing in.
Could you please send us the link of the product so that we can ensure which product you are referring to?
With your help, we can find a solution more quickly.
Best regards