• Opto-transmitter / opto-receiver
• Suppressor capacitors
Defective snubber circuit capacitors may only be replaced on inserted thyristor electronics.
WARNING
Electric shock hazard
The snubber circuit capacitors are not equipped with discharge resistors. The energy stored
in the capacitors is discharged via a circuit in the thyristor electronics. This circuit is
interrupted when the thyristor electronics are withdrawn.
Voltages of up to several 1000 V can occur and cause an electric shock. This can result in
death, severe injuries and significant material damage.
• In this case you should treat the capacitors as if they were charged.
• Discharge the snubber circuit capacitors. Short-circuit the snubber circuit capacitors
before you withdraw the thyristor electronics.
Figure 9-7
Thyristor rack position
9.6.6.2
Replacing thyristor electronics
DANGER
Danger from non-compliance with the 5 safety rules
Non-compliance with the 5 safety rules can cause death or serious injury. Serious material
damage can also result.
• Carefully comply with the 5 safety rules.
• Work must only be performed on adequately grounded power circuitry.
Maintenance
9.6 Repairs
3rd Party LCI Control Upgrade
128
Operating Instructions, 02/2022, A5E31872818