PID problem or not?

[tonycobby]

meg unwinder

hello daved weve got 8 meg splicers where i work,some from the early 90s,and other late 90s.you must have an 80s model that use the meg
tension control card and the seperate box for calculating the diameter.in our older models there is a siemens 135u doing the whole job and in the newer ones i think its a 155u.ill have a look tomorrow
to see if i can find any info on the ajustments,if i cant find anything ill talk to the meg guy, here in spain,he does the refits on there old unwinder im sure he can give me some tips.

 

[tonycobby]

unwinder

hello daved ive got a set of drawings of a dme ´s´ type from 1988.
they use the siemens 135u.the analog out goes through a voltage/current convertor card,probably because the prop valve works on current.the thing is,is that the pressure transducer dosnt go into
the plc,it goes direct to the current convertor card and is added to the plc analog output,possibly theyre using this as damping so as not to have the zero error zero output situation.also in the adjustments
this transducer with near zero air on the brakes is feeding 2.5v into the current convertor card,while at the same time the analog output is 0v.i spoke to the meg guy and hes going to look for info on thier refits,by the way they use the herion valve as well.