5.2.12 Safe Torque O
The Safe Torque O (STO) function is used to stop the
drive in emergency stop situations. The drive can use the
STO function with asynchronous, synchronous, and
permanent magnet motors.
For more information about Safe Torque
O, including
installation and commissioning, refer to the VLT
®
FC Series -
Safe Torque O Operating Guide.
Liability conditions
The customer is responsible for ensuring that personnel
know how to install and operate the Safe Torque
O
function by:
•
Reading and understanding the safety regulations
concerning health, safety, and accident
prevention.
•
Understanding the generic and safety guidelines
provided in the VLT
®
FC Series - Safe Torque O
Operating Guide.
•
Having a good knowledge of the generic and
safety standards for the specic application.
5.3
Specic VLT
®
AQUA Drive FC 202
Features
The VLT
®
AQUA Drive FC 202 is designed for water and
wastewater applications. The wide range of standard and
optional features includes optimized SmartStart and quick
menu with a focus on water and wastewater applications:
•
Cascade control
Basic cascade control is built in as standard, with
a capacity of up to 3 pumps. Cascade control
provides speed control of a single pump in a
multi-pump system. This feature is a cost-
attractive solution for booster sets. Systems with
multiple variable speed pumps require the VLT
®
Extended Cascade Controller MCO 101 or the
VLT
®
Advanced Cascade Controller MCO 102.
•
Motor alternation
The motor alternation functionality is suitable for
applications with 2 motors or 2 pumps sharing 1
drive.
•
Flow compensation
Flow compensation adapts the setpoint according
to the ow, enabling mounting of the pressure
sensor close to the pump.
•
Dry-run detection
The feature prevents damage of the pump by
avoiding dry-running and pump overheat.
•
End-of-curve detection
The feature detects when the pump is running at
maximum speed and the setpoint cannot be
reached for a user-dened time period.
•
Deragging
This preventive or reactive cleaning feature is
designed for pumps in wastewater applications.
See chapter 5.6 Deragging Overview for details.
•
Initial/nal ramps
Programming of short ramp times to/from
minimum speed protects bearings, and ensures
sucient cooling in applications with submersible
pumps.
•
Check valve protection
A slow ramp-down rate protects check valves and
prevents water hammering.
•
STO
STO enables safe torque o (coast) when a critical
situation occurs.
•
Low-ow detection
This feature detects no-ow or low-ow
conditions of the system.
•
Sleep mode
The sleep mode feature saves energy by stopping
the pump when there is no demand.
•
Pipe ll mode
Pipe ll mode comprises functionalities to ll
pipes smoothly and avoid water hammering. This
feature provides dierent modes for horizontal
and vertical pipes.
•
Real time clock
•
Smart logic control (SLC)
SLC comprises programming of a sequence
consisting of events and actions. SLC oers a
wide range of PLC functions using comparators,
logic rules, and timers.
•
Pre/post Lube
See chapter 5.7 Pre/post Lube Overview for details.
•
Flow conrmation
See chapter 5.8 Flow Conrmation Overview for
details.
•
Advanced minimum speed monitoring for
submersible pumps
See chapter 5.9 Advanced Minimum Speed
Monitoring Overview for details.
•
Preventive maintenance
The preventive maintenance feature enables
programming of scheduled service intervals into
the drive.
Product Features Design Guide
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