How to seperate HTTP requests in time?

I’m using 3 HTTP requests to get data. That is working fine, however I’m observing every now and then an Error like:

12:30:12.452 [ERROR] [ab.binding.http.internal.HttpBinding] - No response receiv                                                                                        ed from 'Abfrage3'

With “Abfrage3” being one of the requests.
They all have an updateintervall of 300000 (i.e 5 minutes). I think the problem migth be that they are all calling the same server and they are coming in rigth after each other. Therefore I’m looking for a way to seperate them in time.