AC / DC Drives

EEC is a leading supplier of AC / DC Drives. We stock an extensive range of drives together with a range of ancillary products. We are able to support obsolete drives as we stock a broad range of spare parts and drives. We supply medium voltage variable speed drives for a wide range of applications in the cement, mining and minerals; power; water; metals; marine and chemical, oil and gas industries. They are used to adapt the motor speed to the actual need, thus optimizing energy consumption. Our product portfolio also includes state-of-the-art DC drives which gives you design flexibility and the proven dependable performance.

EEC assists its customers in improving productivity and reducing energy consumption with a comprehensive, range of AC drives and drive systems. Our offering of AC drive products are sold with solutions from simple speed control to complex coordinated process control.

AC Drives

An AC Drive is an electronic device that converts a fixed frequency and voltage to an adjustable frequency and AC voltage source. It controls the speed, torque, horsepower and direction of an AC motor. AC Drive is also a term used for an AC inverter and is sometimes used to describe a particular section of an AC drive. The section uses the DC voltage from a previous circuit stage (DC Bus) to produce an AC current or voltage having the desired frequency.

AC Drives are also referred to as Variable Frequency Drives (VFD's) or Adjustable Speed Drives (ASD's). These drives are gaining in popularity due to the energy savings that can be obtained related to the AC technology. In addition, AC motors are simpler than DC and usually an "off-the-shelf" item compared to DC motors. Advances in technology have made the size, cost, reliability and performance of AC drives very appealing in industrial variable speed applications.

Today the variable-frequency drive is perhaps the most common type of output or load for a control system. As applications become more complex, the frequency drive has the ability to control the speed of the motor, the direction the motor shaft is turning, the torque the motor provides to a load and any other motor parameter that can be sensed. Newer drives have a variety of parameters that can be controlled by numbers programmed into it or downloaded from another microprocessor-controlled system such as a programmable controller (PLC).

DC Drives

Despite the popularity of AC drives, DC drives have favorable characteristics that prove to be appropriate for many applications. The characteristics of a DC Drive include: speed changes that are made by increasing or decreasing the amount of DC voltage fed to the motor from the drive, low cost for medium and high HP applications, wide speed range and good speed regulation. DC drives can also be very compact in size.

DC drives are best used in applications where:

The DC motor exists in a reasonably clean and dry environment, and the use of DPG, DPG-FV, TENV, or TEFC motor enclosures is required.
The application requires a wide range of changing loads.
Motor speeds can reach 2500 RPM
Starting torque is greater than 150% or unpredictable.
Application HP requirements are medium to large.

Our AC-DC portfolio includes world class brands and models like:

ABB
ACS55 [0.25-3 HP] (0.18-2.2 kW)
ACS150 [0.5-5 HP] (0.37-4 kW)
ACS250 [0.5-20 HP] (0.37-15 kW)
ACS355 [0.37 to 22 kW] (0.5 to 30 HP)
ACS850-04 [0.37 to 560 kW] (0.5 to 700 HP)
ACS310 [0.37-22 kW] (0.5-30 HP)
ACS550-01 wall-mounted units [0.75-160 kW] (0.5-200 HP)
ACS550-02 free-standing units [160-355 kW] (250-500 HP)
ACS550-U1 [0.75-150 HP] (240-600V)
ACS800 single drives [0.55 to 5600 kW]
ACS800 multidrives [1.5 to 5600 kW]
ACS800 drive modules [1.1 to 4000 kW]
DCS 800
DCS 550

AF-650 GP* General Purpose Drives
AF-60 LP* Micro Drives
V-300 Standard Drive

Schneider

Altivar 61
Altivar 71

Siemens

SINAMICS V90
SIMOTICS S-1FL6
G110
G120
G130
M410
M420
M430
M440
SIMOREG DC Master
SINAMICS DCM
SIMOREG CM

Parker Hannifin

Parker 650 Inverter Series
Parker 690 Inverter Series
Parker AC30V Inverter Series
Parker 890 Inverter Series
Parker 512C / 514C Series
Parker 590 Integrator Series

Rockwell / Allen Bradley

Power Flex 4
Power Flex 40
Power Flex 400
Power Flex 70
Power Flex 700
Power Flex 7000
20P Power Flex DC

Delta

VFD L
VFD M
VFD EL
VFD B
VFD VE

Yaskawa

A1000
V1000
V1000-4X
J1000
F7
G5
G7

Danfoss

VLT Micro
VLT 2800
VLT-5000
VLT-6000
FC300
FC 301
FC 302

Most of the common models are generally readily available with us.