Mr. Geo

Dear sir,

i am using simodrive Model: 6SN1118-0NK01-0AA1 and getting error E-b608 everyday if restart machine several times error will disappear. To overcome this i changed power cable, encoder cable and even i swap the motor between A&B axis to check is any encoder of B axis  damaged but even still same error E-b608 only appearing.

I request forum to support me overcome this issue 

Hello Mr. Geo, 

Welcome to forum.

Alarm no 608 - is speed controller at its limit for longer time set in p1605. Since you mentioned, this problem triggers daily when you restart the machine & all other possible causes have been tried out, I suggest you below points.

1. Check that axis if any external brake or overloading is causing at start.

2. Check the DC bus value, if it is getting develop late. Check & tight the connections of DC bus links, motor cable, motor terminal etc. etc.

3. Check motor IR value & cable for any short circuit, specially motor cable insulation damage.

4. Try by swapping drive LT module of same capacity with another LT module & check if problem shifts.

Hope this helps.

 Hi, Friend, PICSEAN already answered your in very detail. I want give some troubleshooting tips from another angle.

Error 608 is a very common error and some times it is a headache for us. 

1st of all you already did something correct , suggest you continue doing from simple action. such as change drive , Siemens call power section --you have a double axis system B has error you switched motor the error is still on B side , now change power section, to a new or known good one.

2nd. one of the troubleshooting tips --is knowing machine history. you can think how long this error happened , compare machine working condition and environment before and after.

3rd. from mechanical side , if your motor has brake, check brake active/response , or simply change to new motor, checking brake release power supply and wires , contactor    

Mr. Geo

Dear sir,

i am using simodrive Model: 6SN1118-0NK01-0AA1 and getting error E-b608 everyday if restart machine several times error will disappear. To overcome this i changed power cable, encoder cable and even i swap the motor between A&B axis to check is any encoder of B axis  damaged but even still same error E-b608 only appearing.

I request forum to support me overcome this issue 

Do you have ability to test your drive and servo motor by using SIMO COM U?

 If not! Let repair companies come to your shop, to show you they repaired everything good for running?

You can also send all your hardware to me I can test for you—if you really want run but no local support —PM me for how to do— ship everything to me I can test for you 

when you know all your hardware are in good condition  , you will know where is the problem 

to cause E-608

Shahid Azeemi

Hi everyone. 

I am also facing this problem E-b608 in siemens drive 611. I did every thing that told my friends. We repaired drive from repairng company, thay said drive was faulty and we repaired. But the problem is same. When we start the machine before giving reference, X2 motor slowly moving some time forward and sometimes reverse, and stuck with bearing.  Limits switches also not stopped it. I changed its power module an other but same problem. Some time its moving fast when we give reference be before stuck.and that time error shift to 501 Encoder cable and power cable also checked ✔️. It could be a wiring problem or any relay missing that motor move. Please give me answer.