[RussWhite]

"will check if it will do clamp DC voltage"

I'm going to pick at your terminology a little bit in an effort to help you understand and to correct post for future readers...

When a meter is used in the "clamp on" configuration - that is, you open the jaws and place them around a wire ( conductor ) you will be measuring current, not voltage. That is true whether the clamp on is around a wire carrying AC current or DC current ( Alternating or Direct ). The major difference here is that in the past there were very few reasonably priced clamp on meters that could accurately measure DC current ( the current you would be wanting to measure to check a DC solenoid ). Hall effect sensors ( that were needed to do that ) were expensive and most clamp on meters in the bottom of tool boxes were good only for AC. Thankfully that has changed, and as I posted a reasonably priced clamp on is now not only accurate for DC but affordable for almost anyone.
Just for a rough approximation, the amount of DC current varies in proportion to the size of the solenoid If you measure in the ballpark of 4 amps on those slide solenoids I think you can assume they are getting proper voltage and move on from there. Russ