Danfoss VLT Series Design Manual page 82

3. VLT HVAC Selection
For a more detailed description of parameters, please refer to the
Guide, MG.11.Cx.yy
Real-time clock (RTC) with back-up
The data format of RTC includes year, month, date, hour, minutes and weekday.
Accuracy of clock is better than ± 20 ppm at 77° F [25° C].
3
On average, the built-in lithium back-up battery lasts a minimum of 10 years when the adjustable
frequency drive is operating at an ambient temperature of 104° F [40° C]. If the battery back-up
pack fails, the analog I/O option must be replaced.
3.6.10. Brake Resistors
In applications where the motor is used as a brake, energy is generated in the motor and sent
back into the adjustable frequency drive. If the energy cannot be transported back to the motor,
it will increase the voltage in the drive DC line. In applications with frequent braking and/or high
inertia loads, this increase may lead to an overvoltage trip in the drive, and ultimately, a shut
down. Brake resistors are used to dissipate the excess energy resulting from the regenerative
braking. The resistor is selected in respect to its ohmic value, its power dissipation rate and its
physical size. Danfoss offers a wide verity of different resistors that are specially designed for our
drives. Code numbers can be found in the section
3.6.11. Remote mounting kit for LCP
The local control panel can be moved to the
front of a cabinet by using the remote built-in
kit. The enclosure is the IP 65. The fastening
screws must be tightened with a torque of
max. 1 Nm.
Ordering no. 130B1113
3.14: LCP kit with graphical LCP, fasteners, 9.8 ft
[3 m] cable and gasket.
LCP kit without an LCP is also available. Ordering number: 130B1117
82
.
MG.11.B4.22 - VLT ® is a registered Danfoss trademark.
VLT
®
VLT HVAC Drive Programming
How to order
.
Technical data
Enclosure:
Max. cable length between VLT
and unit:
Communication std:
Ordering no. 130B1114
3.15: LCP kit with numerical LCP, fasteners and
gasket.
® HVAC Drive Design Guide
IP 65 front
3 m
RS-485