4.6 DC braking (n068~n070)
N068 DC braking current (0~100% rated frequency converter, default 50%)
N069 shutdown DC braking time (0.0~5.0 s, default 0.5 s)
N070 starts DC braking time (default 0.0 s)
Used for precise positioning before parking or starting. The larger the braking current, the stronger the braking torque, but the motor heats up more.
4.7 Carrier frequency (n054)
The carrier frequency (IGBT switching frequency) can be set to 1-6, corresponding to 2.5 kHz, 5.0 kHz, 8.0 kHz, 10 kHz, 12.5 kHz, and 15 kHz. The default value is automatically set according to the capacity. Increasing the carrier frequency can reduce motor noise, but it increases leakage current and RFI, and requires derating for use. When the length of the motor cable exceeds 50 meters, it is recommended to reduce the carrier frequency to below 5 kHz.
4.8 Stall prevention (current limiting)
Acceleration stall prevention (n073): If the current exceeds the set value (default is about 170%) during acceleration, the acceleration stops and continues after the current drops.
Constant speed stall prevention (n074): If the current exceeds the set value (default about 160%) during constant speed, deceleration will begin; Accelerate again after the current drops.
Deceleration stall prevention (n072): Prevent overvoltage during deceleration. When connecting an external braking resistor, it should be set to "Disabled".
4.9 Frequency Limitation and Jump Frequency
Frequency upper limit (n031) and frequency lower limit (n032): set as a percentage of the maximum frequency.
Jump frequency (n062~n064): Avoid mechanical resonance points. N062 and n063 are the two hopping center frequencies, and n064 is the hopping bandwidth (±). Satisfy n062 ≤ n063, otherwise report OPE6 error.
4.10 PID Control (n084~n095)
Used for closed-loop control of constant voltage, constant current, constant temperature, etc. Enable n084=1 (standard PID) or 2 (with feedforward). The given value can be set through FV voltage or multi-stage speed, and the feedback value is input through FI (4~20 mA or 0~10 V). parameter
N086 proportional gain (P, default 1.0)
N087 Integral Time (I, default 10.0 seconds)
N088 differential time (D, default 0.00 s)
N089 integral limit (default 100%)
N094/n095 sleep function: When the PID output is lower than n094 and the duration exceeds n095, the inverter stops outputting to save energy.
4.11 MODBUS Communication (n103~n106)
SI-K2/P communication card needs to be installed. parameter
N103 frequency reference unit (0.1 Hz or 0.01 Hz or 0.1%)
N104 slave station address (1-31)
N105 baud rate (2400/4800/9600 bps)
N106 parity check (none/odd/even)
Communication can achieve start stop, frequency setting, parameter reading and writing, fault reset, etc. Select 'COM' as the source for SEQ or REF in n002.
4.12 Multi functional Input/Output Programming
Multi functional input (n036~n040): The S2~S6 terminals can be defined as 28 functions, including external fault, fault reset, multi-stage speed command 1/2, jog, acceleration/deceleration time switching, speed search, PID disable, etc.
Multi functional output (n041, n042): M1 and M2 can be defined as 17 types of signals including running, consistent frequency, over torque detection, base blockade, ready, timer output, etc.
Frequency consistency detection (n075): Set a frequency comparison threshold and cooperate with the output terminal to achieve speed arrival indication.

Chapter 5: Fault Diagnosis and Maintenance - Quickly Locate Problems
5.1 Fault Display and Handling
When the protection function is activated, the frequency converter cuts off the output, the motor stops freely, the fault relay acts, and the digital operator displays a fault code. Common faults and countermeasures:
Display the name of the fault, common causes, and handling measures
OC overcurrent output short circuit, rapid acceleration and deceleration, and excessive load GD ². Check the output insulation; Extend acceleration and deceleration time; Enable speed search
GF grounding fault motor or cable short circuit to ground, shake test insulation resistance; Check the junction box
OV overvoltage deceleration time is too short, load regeneration prolongs deceleration time; Install brake resistor (PC5 series optional)
PUV undervoltage input voltage too low, phase loss check power supply and wiring; Set instantaneous power outage to continue operation
OH1 radiator overheating, high ambient temperature, fan failure, dust accumulation, cleaning of heat sink; Replace the fan; Reduce the carrier frequency
OL1 motor overload and heavy load, long-term low-speed operation to reduce load; Adjust V/f; Check the rated current setting of the motor
OL2 frequency converter overload load exceeds 120% (VT)/150% (CT) for 1 minute to increase frequency converter capacity; Extend acceleration and deceleration time
OL3 over/under torque detection for mechanical faults and load mutation inspection for machinery; Adjust the detection level (n078) and time (n079)
SPI input phase loss three-phase input phase loss inspection power supply and MCCB; Adjust the detection level (n083)
Close the EFx external fault terminal S3 (or set S2~S6 as external fault) and check the external emergency stop circuit