PHP - DateTime->add not working. Says DateInterval format is wrong

Question

I've been struggling for a few hours on an error that I'm sure it's silly, but I can't find to solve it.

My idea is to create a DateTime of (00:00:00), in order to add to it in a loop 4:30 hours per $i.

$saldo_funcionario = new DateTime('00:00:00');
for ($i=0; $i<$value; $i++) {
    $tempo_dia_funcionario = new DateInterval('PT4H30I');
    $saldo_funcionario->add($tempo_dia_funcionario);
}

The error message is:

Fatal error: Uncaught exception 'Exception' with message 'DateInterval::__construct(): Unknown or bad format (PT4H30I)' 
DateInterval->__construct('PT4H30I') #1 {main} on line 75

Where am I missing?

Answer 1

$tempo_dia_funcionario = new DateInterval('PT4H30I');

Should be:

$tempo_dia_funcionario = new DateInterval('PT4H30M');

Notice 'M' instead of 'I'.

http://php.net/manual/en/dateinterval.construct.php