How to increase the https and ssh timeout on a Dell X1052 switch

Hi,

We've recently acquired a couple of Dell X1052 switches and I am looking to configure the ssh timeout.  I've seen other posts mention setting the exec-timeout, but there is no mention of how to set it in the 

Dell™ Networking™ X1000
and X4000 Series Switches
User Guide

I've entered the enable and config commands, but don't see any options for ssh, http or https to set the timeout value.

Any help will be greatly appreciated.

Thanks,

Paul