To make updates to a specific meter, you can make a PATCH call to the meters endpoint. A list of specific fields that can be updated can be found here. Each meter can have up to 10 custom data fields associated. Custom data fields are not required. Custom data allows you to organize meters and tie them back to records in your own system. To update a custom data field, the field must already have a defined label. To define a Custom Data label, you must use the Update Organization Custom Data endpoint.