If your drifting then it sounds like there is no pattern s curve or it has shut down for some reason when the ctw is dragging the car up.

there is a pattern, as the car will run down when the car is in the bottom 2/3 of the hoistway. also it will run up, but at a higher rate then the down. if i start at the bottom, the car will run all the way up at about 25 fpm, it is only at the upper 1/3 of thehoistway that the car will start to not be able to pick up cwt and run down.
im not sure about the open or closed loop operation, if i do the velocity test at 5 fpm, then the car will run in both directions at 5 fpm no matter where it is in the hoistway. this is why I'm thinking maybe on inspection it is running open loop. there are a couple of adjustable resistors in the generator field circuit that are in play when ux and dx are not energized. the output of the scr pack goes thru these resistors when ux and dx are not energized. again I'm not sure about the operation of the motor control under inspection, i can't find any info on how to adjust. i thought it may be load weighting, but the load weigher is functioning, the tool does recognize different weights in the car. when the car is empty the load is displayed as 0 . i don't believe i am just drifting up, as it does seem as it is under control, again it will run the same speed all the way up, thinking maybe a problem with the generator. going to go back and check for grounds in the loop. after thinking about it awhile, maybe I'm getting a ground, although usually when you get a good ground in the loop, the loop fuse will blow, or the loop breaker will blow, maybe it is a high enough ohm ground that it is not blowing the fuse or breaker. there are some load weighing adjustments and gain adjustments on the amplifier board, but i did not want to start tweaking them, as the car runs fine on normal.

Ok so the main issue is down direction on inspection, but do you still drift up when trying to go down? That to me still indicates a loss of pattern or at least enough to stall. I seem to remember sometimes they may just shut off the output when it goes beyond a point of no return, but cant remember if its this type. The fact that it runs ok on normal indicates that the generator is ok( ie no grounds as at full speed this would happen even more I would think) and the fact that it drives at other points and speed would indicate the inspection control is working ( assuming that your doing it from both the car top and the controller for the same result). I also thought of the load weighing but you have cleared that, so it does look like its a drive output difference. Have you tested the voltage at the motor fields, armature when going up/down?

Edit: from further thought I think you get what I call a pattern (profile generation) from the processor but it also goes into the amp for the generator field, so you could check the difference on that output when driving up and down. Also I think I remember that the load weighing should read around 80 pounds no load. Having zero may not pre load the lift. Also make sure your spring on the PVT isn't broken. Just spit balling here as it has been 15 years since I worked on a 401.

If you are picking the Brake to run the CPU thinks everything is OK, therefore whatever tells the Generator Field to Ramp up is not working, or some sort of ground in the Brush Rigging that only shows up on Inspection. If you have Motor Field and the Motor Armature is good, the only other place to look is the Generator Field and related circuits on Inspection.

One other thought. How does the Compensating Ropes and Pit Sheaves look.

Yep, so if your IGF is the same voltage but the polarity is reversed (profile pattern up and down) then the profile or ramp would indicate its ok, then there may be a small generator leak somewhere. If it isn't then the either the processor isn't pumping out the right profile, or something else is stopping it from doing it.

Hello
Does anyone have the software for diagnosis in Elevonic 401? It is possible to send me?

almost forgot about this post, sorry guys, found the solution, while digging thru some notes that a former mechanic had left, i found a section that showed the second pot down from the top on the old power amplifier board, it had a note on it that said to adjust to equal the up and down inspection speeds. i had to turn it 6 turns ccw, and now the inspection works fine. go figure. maybe the generator is getting a little weak, and finally that pot had to be adjusted, in any case, it works now.