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MAKING MODERN LIVING POSSIBLE www.danfoss.com/drives S S ervice Manual VLT Soft Starter - MCD500 175R0550 MG17L402 Rev. 2010–11–05 *MG17L402*...
4.6 Power Assemblies 4.7 Snubber Assemblies 4.8 Fans 4.9 Current Transformers 4.10 Bypass Contactors 4.11 Plastics 4.11.1 Complete Plastics 4.12 Bus Bars 4.13 Other Spare Parts 5 Avoiding Damage 5.1 SCRs ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
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5.2.1 Using the Soft Starter to Switch a Contactor 5.3 Control Input 6 Appendix 6.1.1 Input/Output Busbars to SCRs 6.1.2 SCRs to Heatsink 6.1.3 Bypass Contactor Connections 6.1.4 Current Transformer Busbar Assembly ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
If the starter is installed without a main according to local and currently valid contactor, the bus bar and heatsink are live whenever mains legislation. voltage is connected (including when the starter is ready or tripped). ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
SCR(s) and checking for correct operation. contactors. Use this test if the starter trips with "Bypass Fail" Investigate the likely cause of SCR damage to or "Time Overcurrent". prevent a repeat SCR failure. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
Ensure that the welcome screen displays the correct Control/Mode/HMI firmware versions. Perform a Run Simulation test using both the LCP and remote switches. Connect mains supply and motor. Test that the soft starter functions as expected. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
(shearpin) while running. This may indicate a jammed load. Related Pars.: 2-6, 2-7, 16-4 Internal Fault X The MCD 500 has tripped on an internal fault. Contact your local supplier with the fault code (X). Related Pars.: None ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
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The phase sequence on the soft starter's input terminals (L1, L2, L3) is not valid. Check the phase sequence on L1, L2, L3 and ensure the setting in Par. 2-1 is suitable for the instal- lation. Related Pars.: 2-1 ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
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(shafts, belts or couplings), or a pump running dry. Related Pars.: 2-4, 2-5, 16-3 Unsupported Option The selected function is not available (e.g. jog is not supported in inside delta configuration). Related Pars.: None ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
- The soft stop settings may not be appropriate for the motor and load. Review the settings of Pars. 1-10, 1-11, 7-10 and 7-11. - If the motor is very lightly loaded, soft stop will have limited effect. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
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- The EEPROM may be faulty on the Main Control PCB. A faulty EEPROM will also trip the soft starter, and the LCP will display the message Par. Out of Range. Contact your local supplier for advice. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
MCD 500 Service Manual 3.1.1 MCD5-0021B - MCD5-0053B (G1B) 177HA536.10 Cover Current transformers Cable guide Mounting posts Main plastic Backplane PCB Terminal blocks SCRs LCP and Main Control PCB Side plastic Model PCB ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
3.1.2 MCD5-0068B - MCD5-0105B (G1B) 177HA537.10 Cover Mounting posts Cable guide Bypass contactors Main plastic Backplane PCB Terminal blocks SCRs LCP and Main Control PCB Side plastic Model PCB Current transformers ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
3.1.3 MCD5-0131B - MCD5-0215B (G2B) 177HA538.10 Cover Model PCB Main plastic Current transformers Cable guide Bypass contactors Terminal blocks SCRs LCP and Main Control PCB Main body Bypass Driver PCB Fan and bracket Support plastic ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
MCD 500 Service Manual 3.1.4 MCD5-0245C (G3C) 177HA539.10 Cover Support plastic Cable guide Model PCB Main plastic Current transformers Terminal blocks SCRs LCP and Main Control PCB Main body Fan assembly ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
Module mount and spacer plastic Cable guide Fan assembly Support plastic Power assembly Model PCB Current transformer assembly Module mount and spacer plastic Main body Magnetic bypass plate (models <0595>C ~ 0927C) ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
Cover Snubber assembly Main plastic Magnetic bypass plate Cable guide Power assembly LCP and Main Control PCB Fan assembly Bypass driver PCB Current transformer assembly Support plastic Main body Model PCB ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
Spare part kits may onclude either Semikron or Eupec SRCs. These SCRs are fully interchangeable in MCD 500 units and can be mixed within the same soft starter. Model 0021 - 0068 SEMIKRON EUPEC ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
MCD5-0619C MCD5-0790C MCD5-0927C MCD5-1200C MCD5-1410C 175G5700 MCD5-1600C 175G5699 175G5700 4.8 Fans Certain models include a fan. The number of fans required differs between units and is shown in the table below. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
Semiconductor fuses reduce the potential for SCR damage caused by short circuits on the output of the starter. Protection systems such as circuit breakers or HRC fuses do not operate quickly enough to protect SCRs from short circuits. ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
If long cable runs are used, wiring must be twisted 1. Soft starter output relay pair or shielded cable and must be separated from 2. Slave relay coil AC power cables by at least 300 mm. 3. Contactor coil ® MG.17.L4.02 - VLT is a registered Danfoss trademark...
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