[TYPO3-mvc] Get related 1:n object from external class

[Henry DoShell]

Hi,

think this is a newbie question. In my model "room" that contains the object "roomrate" I've a 1:n relation to an external class "conversionrate" with the object "conversionratenum". Now I need to multiply the objects "roomrate" and "conversionratenum" , but I am not able to get the correct value, its null:

/**
* Returns the sellingrate
 *
* @return \float $sellingrate
*/
public function getSellingrate() {
	return $this->roomratenum * $this->conversionratenum;
}

All repositories and injections are made, in frontend everything is all right.

Think I have to set the external class in reflection part. Could please someone push me in the right direction?

Thnks
Henry