We use visualsvn with tortoiseSVN on the client for version control of the binaries. That is, when we want to test a project, the test branch is merged with the build branch. Th
HTTP status code 502 is a server side error:
RFC 7231 section 6.6.3:
The 502 (Bad Gateway) status code indicates that the server, while acting as a gateway or proxy, received an invalid response from an inbound server it accessed while attempting to fulfill the request.
As you are checking in binary files it could be a timeout from a server between you and the svn servern as the checking takes too long. So you should check the svn server and any server between you and the svn server.