I need to install 2 power circuits to a single pole rcd

It needs a service to clear the filters and more. Take it to the closest service agent.

Check with your nearest dealer or the shop where you have purchased the product.

Here is a link to one of them - http://www.springfieldprecision.com/wp-content/themes/starkers/style/manuals/manual-91455sfd.pdf - you can replace the model with your specific model to see your manual. The site doesn't work correct to do a search. Hope this helps.