Safety
information
Product
information
Mechanical
installation
Electrical
installation
Getting
started
Basic
parameters
Running the
motor
Optimization
NV Media Card
Operation
Building
Automation
Advanced
parameters
Technical
data
Diagnostics
UL listing
information
HVAC Drive H300 317
Issue Number: 3
14.7 Motor overload protection and thermal memory retention
All drives incorporate internal overload protection for the motor load that does not require the use of an external or remote overload protection device.
The protection level is adjustable and the method of adjustment is provided in section 8.2 Motor thermal protection on page 160. Maximum current
overload is dependent on the values entered into the current limit parameters (motoring current limit, regenerative current limit and symmetrical
current limit entered as percentage) and the motor rated current parameter (entered in amperes).
The duration of the overload is dependent on motor thermal time constant. The time constant is programmable. The default overload protection is set
such that the product is capable of 150 % of the current value entered into the motor rated current parameter for 60 seconds.
The drives are provided with user terminals that can be connected to a motor thermistor to protect the motor from high temperature, in the event of a
motor cooling fan failure.
The method of adjustment of the overload protection is provided in the Installation Instructions shipped with the product.
All models are provided with thermal memory retention.
14.8 Electrical supply
The drives are suitable for use on a circuit capable of delivering not more than 100,000 RMS Symmetrical Amperes, at rated voltage when protected
by fuses as specified in the Installation Instructions.
Some smaller drives are suitable for use on a circuit capable of delivering not more than 10,000 RMS Symmetrical Amperes, at rated voltage when
protected by circuit breakers as specified in the Installation Instructions.
14.9 External Class 2 supply
The external power supply used to power the 24 V control circuit shall be marked: "UL Class 2". The power supply voltage shall not exceed 24 Vdc.
14.10 Requirement for Transient Surge Suppression
This requirement applies to drives with rated input voltage = 575 V, Frame Size 7 only.
TRANSIENT SURGE SUPPRESSION SHALL BE INSTALLED ON THE LINE SIDE OF THIS EQUIPMENT AND SHALL BE RATED 575 Vac
(PHASE TO GROUND), 575 Vac (PHASE TO PHASE), SUITABLE FOR OVERVOLTAGE CATEGORY III, AND SHALL PROVIDE PROTECTION
FOR A RATED IMPULSE VOLTAGE TO WITHSTAND VOLTAGE PEAK OF 6 kV AND A CLAMPING VOLTAGE OF MAXIMUM 2400 V.
14.11 Group Installation and Modular Drive Systems
Drives with DC+ and DC- supply connections, with 230 V or 480 V supply voltage rating, are UL approved for use in modular drive systems as
inverters when supplied by the converter sections: Mentor MP25A, 45A, 75A, 105A, 155A or 210A range manufactured by Nidec Industrial
Automation.
Alternatively, the inverters may be supplied by converters from the HVAC Drive-H300 range manufactured by Nidec Industrial Automation.
In these applications the inverters are required to be additionally protected by supplemental fuses.
Drives have not been evaluated for other Group Installation applications, for example where a single inverter is wired directly to two or more motors.
In these applications, additional thermal overload protection is needed. Contact Nidec Industrial Automation for further details.
To Next Page
Loading...
