The Emoncms outputs are handled a little differently from other outputs. When you look at the Emoncms inputs display, all inputs are numbered, and optionally named.
When uploading data, there are protocols that use the number and protocols that use the name. IoTaWatt uses the number for two reasons:
Inputs are not required to have a name
The bulk protocol that IoTaWatt uses to upload uses a positional notation corresponding to each inputs number, which is much more size efficient in data transmission.
So the problem is that you have named the input Wh rather than assign a number, so the app is not accepting it. You should have gotten a validation message for the name and I’ll look into that, but if you change the “Name” to a number, the Save button should appear. If you specify a number that is already in use, this new definition will replace it. If the new number is unique, it will add it to the list of uploads. Look at your existing Emoncms outputs to determine the next number to assign.
From the IoTaWatt Emoncms chapter in the documentation:
One distinctive feature of this list vs the outputs list is that the names must be numeric values between 1 and 99. The name of an entry corresponds to the Emoncms input “key” value. When editing the various fields, if you add a new entry with the same number as an existing entry, or change an entry to the same number as an existing entry, it will replace the existing entry. Each time you save an entry, the list will be reordered.