Hi Guys ,
I'm trying to setup the huawei b593 as wan 2 for load balancing can anyone give me some pointers.

Cheers
Martin

never tried with a 4G modem but you need to set it at any kind of bridge mode or modem only if is possible

before that, set Wan>general set up >wan 2 enable, always on, not sure if needs other settings such vlan etc but it should not
wan > internet access > details page PPPoE tab, if needs password /username - static ip add accordingly & connection detection always on

Then cable from the Lan port (perhaps Lan 1) of the b593 to the wan 2 of the 2830

If there is not any kind of bridge or modem only mode then you may need change the ip address of the modem or the draytek & set the draytek with static or dynamic ip
here i have an example only changing the settings of the first modem
(option 2)
http://www.forum.draytek.co.uk/viewtopic.php?f=2&t=19712#p81508

once both wans are working here for load balance
http://www.draytek.com/index.php?option=com_k2&view=item&id=5181:policy-route&Itemid=293&lang=en
http://www.draytek.com/index.php?option=com_k2&view=item&id=1810:faq-article-1810&Itemid=293&lang=en
http://www.abptech.com/blog/draytek-2920n-automatic-load-balancing-configuration
https://www.draytek.co.uk/archive/kb/kb_load_balancing.html