A small caveat
The science rewards are fairly low for the time invested, trickling in over a long time period, and there is currently a bug (fixed as at 1.7.1 breaking ground) that will log a new notification for very frequent and insignificant science amounts that can lag your game and takes a lot of clicking to dismiss (we're talking about individual messages in your inbox for .04 science points); if you decide, despite the low value, buggy setup (I lose deployed science units through the ground or they just roll away after deploy all the time), and not at all designed balance and messaging you still want to go forward, read on!
The system is evidently somewhat finicky about the order in which various elements are placed down; place them out of order and the parts won't connect properly. For a given cluster of experiments (all controlled by one control station, see the Elements section), the following deployment order seems to be necessary:
- Control station
You'll know things are working after step 3 if the control station thinks it's connected to all the placed experiments and comms, but complains about insufficient power. Adding sufficient power components (step 4) should now cause the control station to receive power. Note that if you move the control station for any reason, you'll need to re-deploy *all* of the power components. And if you add additional experiments, they won't be detected until the control station is re-deployed.
- Control: every setup requires a control station, which can control unlimited experiments so long as there is enough power; all linked units must be within a short (configurable) range around the control unit, default is 50m; no bonuses applied when deploying a control unit. Note that there should be *only one* control station per setup, and control stations should not be allowed to overlap (overlaps cause power producers and experiments to become confused about which control station they belong to, frequently resulting in one control station having all the solar panels while another one has all the experiments).
- Power: Solar Panels will provide power while on the sunny side of body, RTGs will work day and night; by default they provide 1 power unit; an engineer will add another power unit by deploying them and another additional power unit for every 2 stars they possess (i.e. 0⭐=2, 2⭐=3, 4⭐=4); you require 1 power unit for everything that isn't a solar panel or RTG
- Comms: the control setup provides short range comms but you'll usually want to send along a Communatron to extend the range just to reach a relay in many cases (I think the control station has a range analogous to a probe core without additional antennae); expect frequent comms blackouts if you don't have a communatron (which will create more spam messages); no bonuses applied when deploying a comms unit
- Experiments: Most of the experiments are passive but there's an impact one that you need to ram a craft into the body at high speed in order to collect, this is actually the best experiment because it's fairly instantaneous (and very kerbal); the weather one requires atmosphere, all of the others work wherever; If a 5⭐ scientist deploys one of these experiments, they can be completed in 160-320 hours (~27-54 kerbin days, 100% rate), and a non-scientist will take 3200-6400 hours (~533-1067 kerbin days, 5% rate). The general formula of the science per hour of modules depends on the scientist's level, the base value and the body science multiplier.
- Collection: the default rate of collection beams up science every 60 seconds (if connected via commnet) and leaves a message in your messages app, given that none of the experiments have a base rate (before body multipliers) above 1 science per hour, you can imagine how little science you'll be getting per message, you can change this by editing config files in new games and with save file editing in the current game (search these directories for ScienceTimeDelay = 60 to find the line to change, this answer is already long), recommend a value around 21,600 (1 day in seconds)