I hope you all do not mind this type of question? But here goes.

I have a radio that will allow NIMH batteries to be charged on board. I need the AC adapter. They sell them, but I have one that fits the connector and is the correct voltage. However the MA rating is almost double that of what is recommended. It (radio) is rated for 450MA and the one I have is 1.25 amp. The tech at Marconi said to use less than 500MA. I don't get it. Current will only flow as needed. It would seem that a larger MA rating would be of no concern? But a lower MA rating may not provide enough power to charge the batteries?
Am I correct? Thanks in advance......John