melodious said:
Won't the CAv3 cut off cruise power the moment it senses input from an installed PAS
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At 20mph or more there's a fine line you need to make whether you want to pedal with cruise control enabled or just switch to a higher power of pedal assist.
'Good' PAS behavior is largely in the eye (or butt) of the beholder - views are about as polarized as bar room arguments about Ford vs Chevy or the splendor of the President as Savior in Chief. So - it's hard to really give good advice....
That said, the CA3 can be configured in a variety of ways that may give a desirable riding experience although the operation may not be exactly as some simple PAS or autocruise systems work.
As with other controller-based autocruise setups, the CA3 autocruise locks the throttle setting when it is held steady for a (configurable) number of seconds at which time the throttle can be released. The effect is exactly as if the rider was holding the throttle at the setpoint. Autocruise drops out when the throttle is applied or the ebrakes applied. The throttle effect is determined by whether the throttle is configured to simply pass through the signal to the controller or to provide true feedback-controlled current, power, or speed limiting. So - autocruise with CA Speed Throttle actually does control speed as does an automotive cruise control - but frankly, Speed Throttle is incredibly annoying for normal throttle operation (this is not the same as controller 'speed throttle' which has nothing do with maintaining fixed vehicle speed - a common misconception).
Applying throttle causes CA PAS to drop out, so normally you don't get to mix the two. However, if there is a PAS unit installed (even a simple PAS wheel) then it's possible to set up the CA so that autocruise/throttle work ONLY when pedalling (or above a minimum speed). In this setup, you set the autocruise using the throttle while pedalling and then turn off the throttle. Power is applied to the autocruise level whenever you pedal - if you stop pedaling, the power stops, but it resumes at the setpoint when you pedal again. So, setting this up with Speed Throttle would make the bike go to the preset speed whenever you pedaled.
Alternatively, you can just set up PAS and skip the autocruise thing altogether. Here you pedal and you get power. The CA has ramping adjustments to control how aggressively both regular throttle and PAS are applied so you can make the PAS come on gently while the throttle stays snappy.
Most of the cool stuff comes from using an external Aux Input to the CA3 using either a pot or the new digital aux Up/Down button control. This can be configured to limit speed, current, power, or the level of PAS assistance. With PAS, this is typically setup of PAS limiting to simulate the kind of PAS level you get on controllers. However, in this case, the OP might the absolute max speed for say 25mph and then set up an Aux control for speed limiting. The control would then allow adjustment to limit speed anything less than 25mph. Using a simple PAS wheel, the PAS assist power might be set to several hundred watts to be able to achieve 25-30mph. Riding with this setup, the throttle would work normally for general riding, however, if you turn the throttle off and just pedal, the PAS will apply power that will be limited by the speed set on the Aux control - say 20mph. You adjust the PAS ramping to get a gentle power application. If you pedal harder, the CA will back off power to limit speed to 20mph. If you exceed 20mph pedaling, the CA will turn off the power. The Aux control lets you adjust the speed on the fly.
When used with a DD motor and a Phaserunner or Grinfineon controller, the CA3 can also regulate regen to control speed. By enabling this feature, with the Aux input set for Speed Limiting, you can dial up a speed when you go down hills and the CA will apply regen to hold that max speed - no ebrakes need be applied - it just does it. If combined with the PAS setup described above, the PAS will run the bike up to the set speed when you pedal and will smoothly cut power and switch over to regen if the bike goes faster than 20mph (either by pedaling or downhill). This speed-based configuration works seamlessly and for not-flat terrain avoids the on-the-fly speed/power adjustments required to maintain speed as when using the more familiar PAS Assist level control type.
The CA supports simple PAS wheels as well as a variety of more expensive torque-based sensors. The CA3 torque-based PAS is quite impressive with smooth operation and a really bike-like power increase with increased rider effort. That said, the simple PAS wheel can be configured to work very nicely - even to increase power with rpm to get a boost when you downshift. This opens the possibility of a cheap 'starter sensor' and an open path to future upgrade to a better sensor in the future.
Some of these features are available in the 3.1 beta firmware so a programming cable is needed to flash the new firmware over the installed production 3.0 code.
Anyhow, long post, but as you can see, there's a variety of setups possible so "will the CA3 do so-and-so" can be a little slippery to answer. But - one or more configurations may work for you.
