Do a Google search for "electrical tester".
This is one of the things that came up for me:
http://www.globalindustrial.com/p/tools/test-measurement/Metrs-HVAC-R/gardner-bender-gfci-outlet-tester-120-vac?infoParam.campaignId=T9F&gclid=CjwKCAjwk4vMBRAgEiwA4ftLs6XaP9vf4CEG5S0ZJcFPIg4nyPMhResJOH6A-tW2s06tYAslpV-IIxoC0bkQAvD_BwE
It is a simple quick test for "major" faults only and you would need an adapter to test 30 amp outlets. It will NOT completely test a 50 amp outlet.
More complete tests are included with a medium to high end "surge protector", often prices around $100 or more.
It depends on what your budget is and how thorough you wish to be.
'07 Damon Outlaw 3611
CanAm Spyder in the "trunk"