Alternator Problems

Hello everyone,
I am new to this form and have a problem that is giving me tons of trouble. I have a 94 caravan that i just replaced the engine in, however i am having trouble getting the alternator to put out a charge. I have had the alternator tested twice and it passed both times. so i know the problem lies somewhere else. This is where i am stuck im not sure where i should begin checking or what might be wrong. Any suggestions are welcome.

Remember to start with the basics, check the grounds, check connections, etc.

i think ther is a fusible link between the alt and the pdc or battery? you might want to check for it!