
u
Installing Fuses on the Input Side
Always install input fuses to the input side of the as a protective measure against damage caused by a short circuit.
Refer to Standards Compliance on page 463
for details on input fuse selection.
u
Attachment for External Heatsink
An external attachment can be used to project the heatsink outside of an enclosure to ensure that there is sufficient air circulation
around the heatsink. This installation method still requires a certain amount of airflow over the drive case.
Current Derating Due to Ambient Temperature on page 351
if derating is required. Contact a Yaskawa sales representative
for more information.
u
Noise Filter Installation
This drive has undergone testing in conformance with IEC/EN 61800-5-1 and is in compliance with low voltage directives.
Refer to EMC Guidelines Compliance on page 469
for information on selecting a noise filter.
u
Installing a Motor Thermal Overload (oL) Relay on the Drive Output
Motor thermal overload relays protect the motor by disconnecting power lines to the motor due to a motor overload condition.
Install a motor thermal overload relay between the drive and motor:
• When operating multiple motors on a single AC drive.
• When using a power line bypass to operate the motor directly from the power line.
It is not necessary to install a motor thermal overload relay when operating a single motor from a single AC drive. The AC
drive has UL recognized electronic motor overload protection built into the drive software.
Note:
Disable the motor protection function (L1-0 1 = “0”) when using an external motor thermal overload relay. The relay should shut off main
power on the input side of the main circuit when triggered.
n
General Precautions when Using Thermal Overload Relays
The following application precautions should be considered when using motor thermal overload relays on the output of AC
drives in order to prevent nuisance trips or overheat of the motor at low speeds:
• Low speed motor operation
• Use of multiple motors on a single AC drive
• Motor cable length
• Nuisance tripping resulting from high AC drive carrier frequency
Low Speed Operation and Motor Thermal oL Relays
Generally, thermal relays are applied on general-purpose motors. When general-purpose motors are driven by AC drives, the
motor current is approximately 5 to 10% greater than if driven by the commercial power supply. In addition, the cooling
capacity of a motor with a shaft-driven fan decreases when operating at low speeds. Even if the load current is within the motor
rated value, motor overheating may occur. A thermal relay cannot effectively protect the motor due to the reduction of cooling
at low speeds. For this reason, apply the UL recognized electronic thermal overload protection function built into the drive
whenever possible.
UL recognized electronic thermal overload function of the drive:
Speed-dependent heat characteristics are simulated using
data from standard motors and force-ventilated motors. The motor is protected from overload using this function.
Using One Drive with Multiple Motors
Turn off the electronic thermal overload function. Please refer to the appropriate product instruction manual to determine
which parameter disables this function.
The UL recognized electronic thermal overload function of the drive cannot be applied when using multiple motors on one
drive.
Long Motor Cables
When long motor cables and high carrier frequency are used, nuisance tripping of the thermal relay may occur due to increased
leakage current. Therefore, reduce the carrier frequency or increase the tripping level of the thermal overload relay.
Nuisance Tripping Resulting from High AC Drive Carrier Frequency
Current waveforms generated by high carrier frequency PWM drives tend to create additional temperature rise in overload
relays. Therefore, it may be necessary to increase the trip level setting when encountering nuisance triggering of the relay.
8.4 Installing Peripheral Devices
YASKAWA ELECTRIC SIEP C710606 18F YASKAWA AC Drive – V1000 Technical Manual
335
8
Peripheral Devices & Options