{"id":105,"date":"2020-01-13T15:23:42","date_gmt":"2020-01-13T20:23:42","guid":{"rendered":"https:\/\/pressbooks.bccampus.ca\/basicmotorcontrol\/?post_type=chapter&p=105"},"modified":"2020-08-14T18:42:18","modified_gmt":"2020-08-14T22:42:18","slug":"common-issues","status":"publish","type":"chapter","link":"https:\/\/pressbooks.bccampus.ca\/basicmotorcontrol\/chapter\/common-issues\/","title":{"raw":"Common Issues","rendered":"Common Issues"},"content":{"raw":"This chapter will be focusing on troubleshooting common problems found in the [pb_glossary id=\"798\"]power<\/strong>[\/pb_glossary] and [pb_glossary id=\"796\"]control circuits<\/strong>[\/pb_glossary]. Troubleshooting motors and the mechanical systems they drive is an extensive topic beyond the scope of this text.\r\n\r\nA motor may not start for a variety of reasons. Knowing what to check for and where to begin is a valuable skill that can reduce downtime when a fault occurs.\r\n\r\nUsually, there are two fundamental steps in troubleshooting. The first is a cursory visual inspection, followed by a more in-depth examination with testing equipment and referencing several diagrams\r\n\r\nMotor control circuits have several protective devices built into them to protect wires and equipment. It is always a good idea to start your visual inspection by checking overload and overcurrent devices. A visual inspection sometimes quickly locates a fault or identifies situations requiring maintenance. For example, you might see a tripped indicator on a [pb_glossary id=\"888\"]circuit breaker<\/strong>[\/pb_glossary], [pb_glossary id=\"764\"]switch<\/strong>[\/pb_glossary] or [pb_glossary id=\"787\"]overload relay<\/strong>[\/pb_glossary]. Resetting the device might be all the circuit needs to resume working.\r\n\r\nIf an [pb_glossary id=\"690\"]overload<\/strong>[\/pb_glossary] or [pb_glossary id=\"692\"]overcurrent<\/strong>[\/pb_glossary] situation has occurred, it is advisable to find the source of this fault. A visual inspection can identify burnt or heat-discoloured components, loose wires in terminal blocks, or mechanical parts that bind together or cause excessive friction.\r\n\r\nWhen there is no obvious cause for the problem(s), it is often necessary to analyze [pb_glossary id=\"881\"]circuit diagrams<\/strong>[\/pb_glossary] and take measurements of [pb_glossary id=\"718\"]voltage<\/strong>[\/pb_glossary] and [pb_glossary id=\"720\"]resistance<\/strong>[\/pb_glossary] at key points of the circuit. To do this, we use [pb_glossary id=\"883\"]voltmeters<\/strong>[\/pb_glossary] and [pb_glossary id=\"882\"]ohmmeters<\/strong>[\/pb_glossary]. A firm understanding of their use and limitations is necessary for their safe operation in circuits.","rendered":"

This chapter will be focusing on troubleshooting common problems found in the power<\/strong><\/a> and control circuits<\/strong><\/a>. Troubleshooting motors and the mechanical systems they drive is an extensive topic beyond the scope of this text.<\/p>\n

A motor may not start for a variety of reasons. Knowing what to check for and where to begin is a valuable skill that can reduce downtime when a fault occurs.<\/p>\n

Usually, there are two fundamental steps in troubleshooting. The first is a cursory visual inspection, followed by a more in-depth examination with testing equipment and referencing several diagrams<\/p>\n

Motor control circuits have several protective devices built into them to protect wires and equipment. It is always a good idea to start your visual inspection by checking overload and overcurrent devices. A visual inspection sometimes quickly locates a fault or identifies situations requiring maintenance. For example, you might see a tripped indicator on a circuit breaker<\/strong><\/a>, switch<\/strong><\/a> or overload relay<\/strong><\/a>. Resetting the device might be all the circuit needs to resume working.<\/p>\n

If an overload<\/strong><\/a> or overcurrent<\/strong><\/a> situation has occurred, it is advisable to find the source of this fault. A visual inspection can identify burnt or heat-discoloured components, loose wires in terminal blocks, or mechanical parts that bind together or cause excessive friction.<\/p>\n

When there is no obvious cause for the problem(s), it is often necessary to analyze circuit diagrams<\/strong><\/a> and take measurements of voltage<\/strong><\/a> and resistance<\/strong><\/a> at key points of the circuit. To do this, we use voltmeters<\/strong><\/a> and ohmmeters<\/strong><\/a>. A firm understanding of their use and limitations is necessary for their safe operation in circuits.<\/p>\n

definition<\/span>