TOPCON / RDS Artemis Problems - Under dosing after a correct calibration

[Humble Farmer]

First time at posting so here goes -
We have an RDS Artemis system fitted to basically a dual hopper accord drill i.e single fan, two metering systems and a single HD Artemis motor driving the pair of metering mechanisms. We had a fault with the motor last year meaning it had to be replaced, but ever since we have experienced under dosing. When we were spring drilling the last of our winter crops in early Feb we put it down to the fact we were trying to drill at 15km/h and putting on 300kg of seed. We got around it by slowing down and it seemed to resolve the problem.
This autumn we are down at 200-220kg/ha and are still having the same issue. We drilled out 1400kg and Artemis thought we had drilled out 2100kg so roughly 30% out. We then recalibrated and got the same result.
We have got the calibration slides open as far as they can, but this has made no difference.
Drive shafts and metering mechanisms are all in good order. The static calibration / purge speed is set to 14km/h.
We have always drilled at 15km/h no problem, but ever since fitting the new motor we have had problems.
Would anyone have any pointers?
Many thanks
James

 

[Devon James]

The chaps at Topcon, what was RDS are very helpful.
Has the calibration quantity number changed on the head unit? It will be under the settings page

 

[yellow belly]

check the simple things first
check you weigher is accurate

try a calibration at 15 k
and at 7 k
is there a difference

is your speed calibration correct

if they are right
then back pressure when the fan is on

 

[TomR]

@Humble Farmer , how did you get on with this? If you are still having some problems then give us a call on 01453 733300 and you will get through to our tech support line. There are some tests you can run to see how the seed flow is working through the drill with the fan running, by using a simulated speed in the yard.

 

[principal skinner]

Back pressure from the fan, either reduce the fan speed, fit air brakes to the coulters or a ventilated distribution head.