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Siemens VB-A Variable Frequency Drives

Variable Frequency Drives

The Bypass Options are companion packages for the family of SED2 Variable Frequency Drives.

2-Contactor: Output & Bypass:
• Overload protection in bypass mode.
• Step-down transformer with fused primary and secondary.
• Contactors electrically and mechanically interlocked.

3-Contactor (optional): Input, Output, & Bypass:
In addition to the 2-contactor features, 3-contactor features provide:
• Drive test function
• Complete electrical isolation of drive

Input Device:
• Fused disconnect
• Circuit breaker (optional)
• All doors are interlocked and pad-lockable

Reactor Options:
• Line reactor mounted in bypass option enclosure.
• Line reactor (in NEMA 1 enclosure) supplied separately.
• Load reactor (in NEMA 1/3R enclosure) supplied separately. 

Auto Bypass:
• Relay logic allows user to send the motor to bypass mode based on the drive’s programmable relay.
• The drive’s programmable relay, typically set to fault, can be set up for applications that run full speed for an extended period of time.

Enable Input:
• Generally used for safety tie-ins; the motor will not operate the drive or bypass when open.

Common Remote Start/Stop:
• Common remote start/stop can be used in both drive and bypass mode.

Essential Services Mode:
• Typically used for smoke purge; the motor goes to bypass regardless of the selected mode.
• No call to stop will have an effect, including open safety or stop commands.
• Only turning the power off or opening this contact will stop the motor.

2-Contactor Units:
• Drive-Off-Bypass selector
• Bypass pilot light

3-Contactor Units:
• Drive-Off-Bypass selector
• Bypass pilot light
• Drive Test on/off selector

Conventional Bypass Specifications
Input Voltage (3-phase) 208V, 3 AC±10% 1/2 hp to 60 hp (2.3 amps to 154 amps)
240V, 3 AC±10% 1/2 hp to 60 hp (2.3 amps to 154 amps)`
480V, 3 AC ±10%. 1/2 hp to 125 hp (1.2 amps to 178 amps)
575V, 3 AC ±10% 1 hp to 125 hp (2.3 amps to 125 amps)
Protection Level NEMA Type 1
NEMA Type 12
Temperature Operating 32 to 104°F (0 to +40°C)
Storage -40 to +158°F (-40 to +70°C)
Humidity 0 to 95% RH, non-condensing
Drive Specifications
Input Voltage and Power Ranges (3-Phase) 208V and 230V to 240V, 3AC ±10% 1/2 hp to 60 hp
380V to 480V, 3 AC ±10% 1/2 hp to 125 hp
500V to 600V, 3 AC ±10% 1 hp to 125 hp
Input Frequency 47 Hz to 63 Hz
Output Frequency 0 Hz to 150 Hz
Power Factor ≥ 0.9 total, ≥ 0.97 displacement
VFD Degree of Efficiency 96% to 97%
Switch-on Current Less than nominal input current
Auxiliary Supply 24V Glavanically separated, unregulated auxiliary supply (18V to 32V) 100 mA
Overload Capacity 110% for 60 seconds
Control Method Linear, parabolic and programmable V/f;
and flux current control low-power mode
PWM Frequency 2k Hz to 16k Hz (adjustable in 2k Hz increments)
Fixed Frequencies 15 programmable
Skip Frequency Bands 4 programmable
Setpoint Resolution 0.01 Hz digital, 0.01 Hz serial, 10 bit analog
Digital Inputs (Sink/Source) 6: fully programmable and scalable isolated digital inputs, switchable
Analog Inputs 2: 0 to 10 Vdc, 0/4 to 20 mA, can also be configured as digital inputs or Ni 1000 input
Relay Outputs 2: configurable 30 Vdc /5A (resistive),
250 Vac 2A (inductive)
Analog Outputs 2: programmable (0/4 to 20 mA or 0 Vdc to 10 Vdc)
Serial Interface RS-485;
Protocols: USS, P1 and N2;
Transmission rate: Up to 38.4k Baud
Temperature Ranges Operating 14°F to 104°F (–10°C to 40°C)
Storage –40°F to 158°F (–40°C to 70°C)
Humidity 95% rh, non-condensing
Operational Altitudes Up to 3280 ft (1000m) above sea level without derating
Protection Features Under-voltage, Over-voltage, Overload,
Ground fault, Short circuit, Stall prevention,
Locked motor, Motor over-temperature l2 t PTC,
Over-temperature, Parameter PIN protection.
Standards UL, cUL, CE, C-tick
CE Conformity Conformity with EC Low Voltage Directive 73/23/EEC
Options LON Interface, Modbus Interface,
BACnet MS/TP Interface,
Advanced Operator Panel (AOP) Module,
EasyComm Drive Software, PC Kit

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