Transfer all TRX balance from address

[frmiqueias]

I need to transfer all balance from an address, but when I try the default example of sent the transaction is not registered on the network!

$tron->setAddress('address');
$tron->setPrivateKey('privateKey');

try {
$transfer = $tron->send( 'ToAddress', 100.6666);
} catch (\IEXBase\TronAPI\Exception\TronException $e) {
die($e->getMessage());
}

I suspect that the problem is that I send all the amount and there is no balance left for the fee, how could I debit the amount of the fee from the amount to be sent?

Thanks.