Code rH: Braking Resistor Overheat
Issue Description & Safety Warning
The Yaskawa A1000 AC Drive has triggered a critical Braking Resistor Overheat alarm. Immediate attention from a qualified operator or maintenance technician is required to prevent secondary damage to the equipment or spoiled parts during the manufacturing cycle. Always ensure standard safety and LOTO procedures are followed before accessing electrical cabinets.
Official Troubleshooting Steps
Code type: Fault Manual section: Yaskawa A1000 Troubleshooting Deceleration time is too short and excessive regenerative energy is flowing back into the drive. - Check the load, deceleration time, and speed. - Reduce the load inertia. - Increase the deceleration times (C1-01 to C1-08). - Replace the dynamic braking option with a larger device that can handle the power that is discharged. The duty cycle is too high. Check the duty cycle. Maximum of 3% duty cycle is available when L8-01 = 1. Excessive braking inertia. Recalculate braking load and braking power. Reduce the braking load by adjusting braking resistor settings. The braking operation duty cycle is too high. Check the braking operation duty cycle. Braking resistor protection for ERF-type braking resistors (L8-01 = 1) allows a braking duty cycle of maximum 3%. The proper braking resistor has not been installed. - Check the specifications and conditions for the braking resistor device. - Select the optimal braking resistor. Note: The magnitude of the braking load trips the braking resistor overheat alarm, NOT the surface temperature. Using the braking resistor more frequently than it is rated for trips the alarm even when the braking resistor surface is not very hot.
Source: Yaskawa AC Drive A1000 High Performance Vector Control Drive Technical Manual (SIEP C710616 21H)
Last reviewed: 2026-07-01 · Verified against the manufacturer’s official documentation.
About Yaskawa A1000 AC Drive Alarms
Yaskawa controllers include extensive self-diagnostics that flag or halt the machine when a fault is detected. Error code rH on the A1000 AC Drive identifies one specific fault condition — its documented cause and the official corrective steps are listed above, sourced from Yaskawa's service documentation. Always confirm against the manual for your exact machine configuration and follow LOTO procedures before servicing.
Complete Alarm List: 280 Yaskawa A1000 AC Drive codes.
Have a better solution?
Help the industrial community by sharing your repair experience for code rH.
Need a searchable reference for more Yaskawa A1000 AC Drive manuals?
We structure equipment manuals into searchable code, title, cause, solution, safety note, and source-reference data. Send a PDF and example searched codes when you need public pages, private search, or structured exports.
Space reserved for Google AdSense / Industrial Affiliate Links
Monetization target for 2026