Danfoss VLT2807 Compact Frequency Converter

Typical Application Scenarios for Danfoss VLT2807 (0.75 kW)

The VLT2807 is a small-size general-purpose open-loop V/F frequency converter. It supports Constant Torque (CT) / Coppia variabile (VT) selezione, built-in PID and AMA auto-adaptation. Compact side-by-side installation is supported. Mainly used for OEM equipment, HVAC-light-industry and assembly-line drives. Not suitable for high-precision vector control, heavy-shock loads or high-inertia lifting applications.

Stato: Interrotto. Legacy compact general-purpose convertitore di frequenza, 0.75 kW, widely used for fans, pompe, assembly lines and small-size drive equipment.

1. Decodifica del modello (Full-model example: VLT2807PT4B20SBR1DBF12A00C1)

28: VLT2800 series

07: Power rating 0.75 kW / 1HP

P: Process variant

T: Ingresso trifase

4: 380-480 VAC

B: Book-style construction, IP20

R1: Built-in Class A1 EMC filter; R0 = No EMC filter

D: No brake chopper; B = Built-in brake chopper

F12: LCP local control panel; F00 = Without panel

Example order number: 134H2368 (with EMC filter and control panel)

2. Specifiche elettriche principali (380-480 V version)

A single-phase 220 V version VLT2807 (1×220-240 V) is also available, same 0.75 kW power rating, 4.2 A output current.

3. Hardware Interface Overview

Main-circuit Terminals

Ingresso: L1, L2, L3; Motor output: U, V, W; Terra di protezione PE; Brake resistor terminals (selected variants only)

Terminali di controllo (VLT2800 series)

Ingressi digitali: 18, 19, 27, 29, 33

Analogue inputs: 53 (voltage/current), 60 (attuale)

Analogue output: 42

RS485: 68/69 (Profibus-DP via optional expansion card)

Funzioni supportate: Multivelocità, avviare/interrompere, PID, analogue reference, pulse reference, precision stop, auto-restart, AC braking.

4. Caratteristiche principali
5. Quick Menu: Fast commissioning with 12 key motor-setup parameters; supports AMA motor auto-adaptation (Parameter P107).
6. Controllo V/F; selectable constant-torque / variable-torque mode; built-in PID for constant-pressure water-supply and fan applications.
7. Supports brake resistor and AC braking; fault auto-reset and auto-restart.
8. Optional Profibus-DP and DeviceNet fieldbus expansion cards.
9. LCP panel supports parameter copy for batch-unit commissioning.
10. Discontinued-product Replacement Solution

Sostituzione diretta ufficiale: VLT Midi Drive FC280, 0.75 kW, 380-480 V

Highly compatible mounting dimensions and terminal layout; plug-in terminals are reusable; parameters can be migrated.

Added Safe Torque-Off (STO) safety function with enhanced overall performance.

Riferimento alternativo: FC-051 (tipo economico, not direct terminal-compatible; requires full rewiring for retrofit).

6. Codici di errore comuni

Err 8: DC-bus under-voltage. Controllare la tensione in ingresso, supply voltage drop or momentary power loss.

Err 1: Sovracorrente; Err 4: Guasto di terra; Err 14: Guasto a terra; Err 16: Cortocircuito; Err 29: Sovratemperatura.

7. Second-hand Unit Inspection Checklist
8. Controllo visivo: Swollen electrolytic capacitors, PCB corrosion, fan ageing.
9. Power-on without motor: Check for alarms; test all panel keys.
10. Run with small-size motor at no-load; verify three-phase output-voltage balance.
11. Verify power rating, presence of EMC filter and built-in brake chopper.
12. Back-up complete parameter set. Electrolytic capacitors are the main failure risk on this legacy series.
13. Variable-torque loads (Tifosi & Pompe, VT mode)

Torque decreases with speed; energy-saving operation; built-in PID for pressure/flow closed-loop regulation.

1. Piccoli ventilatori centrifughi: Workshop exhaust fans, ventole di raffreddamento dell'armadio, air-handling-unit fans, small waste-gas-treatment fans.
2. Water-supply / pompe di circolazione: Small-scale constant-pressure water supply, cooling-water circulation pumps, pompe dosatrici, process make-up pumps.
3. HVAC terminal-units and small-building ventilation systems.

✅Vantaggi: PID sleep-wake-up function; soft-start to minimise water hammer; notevole effetto di risparmio energetico.

1. Carichi a coppia costante (CT mode, 160 % overload for 1 min)

Torque remains largely independent of speed; sufficient starting-torque required. Mainly for assembly-line and light-industrial machinery.

1. Conveying equipment: Piccoli nastri trasportatori, trasportatori a rulli, chain conveyors, sorting-line equipment.
2. Macchine per l'imballaggio: Piccole macchine confezionatrici, sealers, etichettatrici; precision-stop function for station positioning.
3. Mixing-stirring equipment: Small mixing tanks, blenders and agitators.
4. Light-industry & tessile: Auxiliary drives for small-size unwinding/winding, textile-machinery and cutting equipment.
5. Estrusione & small-process equipment: Micro-extruders, material feeders.

Nota: For long-time operation below 10 Hz, standard-motor cooling deteriorates. Variable-frequency motor with separate cooling fan is recommended.

III. Industry Sectors

1. HVAC: Fans and circulation pumps (most-common application).
2. Confezione & light-industry OEM: Small-power drive units integrated into machinery.
3. Trattamento dell'acqua: Small-size water-supply and chemical-dosing metering pumps.
4. Cibo & bevanda: Small conveyors and agitators.
5. General-factory automation: Auxiliary drives for production-lines.
6. Unsuitable Operating Conditions
7. High-inertia hoisting / lifting machines (only permitted for light-duty auxiliary mechanisms, not for main lifting drives).
8. Applications requiring closed-loop vector control or high-dynamic-response servo-level performance.
9. Continuous heavy-duty operation with frequent shock-loading.
10. Long-term high-speed spindle operation above 400 Hz.
11. Configuration Tips for Typical Applications
12. Fan / pompa: Select R1 variant with built-in EMC filter; set P101 to Variable-Torque (VT).
13. Trasportatore / agitator: Requires high starting-torque; set P101 to Constant-Torque (CT). For frequent braking duty, select variant with built-in brake chopper (suffix-B in model code).
14. Fieldbus control: Add Profibus-DP option card for PLC interfacing.

Complete Technical Specifications of Danfoss VLT2807 (VLT2800 series)

Stato: Interrotto. 0.75 kW, available in single-phase 220 V and three-phase 380-480 V versions.

1. Power-stage Electrical Parameters

① Three-phase 3×380-480 V (widely-used VLT2807PT4)

② Single-phase 1×220-240 V (VLT2807P1)

Valutazione di sovraccarico: Constant-Torque (CT): 160 %, 60 s; Variable-Torque (VT): 110 % continuous.

1. Parametri di prestazione

Control principle: Open-loop V/F control. User-programmable V/F curve; no closed-loop vector capability.

Output-frequency range: 0-1000 Hz; factory default 0-50 Hz.

Carrier switching frequency: 4-16 kHz adjustable, factory default 4 kHz. Current-derating applies at higher switching frequencies.

Motor auto-adaptation AMA: Static AMA supported (P107).

Acceleration / deceleration times: 0.05-3600 s; four independent ramp-time sets selectable.

Built-in PID controller: Closed-loop for fans/pumps; sleep-wake-up, protezione contro il funzionamento a secco, no-flow detection.

Braking modes: AC-braking; optional built-in brake chopper (-B model suffix) for external brake-resistor; DC-bus paralleling for load-sharing.

Restart functions: Fault auto-reset & restart, flying-start, power-drop protection.

III. Control-terminal Ratings

Ingressi digitali (DI: Terminals 18, 19, 27, 29, 33)

Quantità: 5 ingressi digitali; internal 24 V supply; compatible with NPN / PNP logic.

Funzioni: Start-stop, avanti/indietro, multivelocità, fault-reset, pulse reference, output-inhibit.

Analogue Inputs

1. Terminal 53: 0-10 V voltage / 0-20 mA / 4-20 mA, configurabile.
2. Terminal 60: 4-20 mA current-input only.

Uscita analogica (Terminal 42)

1 analogue output: 0-20 mA / 4-20 mA programmable. May output frequency, output-current, output-voltage and other process variables.

Uscita relè

1 uscita relè; contact rating AC250 V / 3 UN. Configurable for fault-signal, drive-running, frequency-reached and other status-signals.

Interfacce di comunicazione

1. Standard: RS485 (Terminals 68/69), supports Modbus-RTU and Metasys-N2 protocols.
2. Optional expansion cards: Profibus-DP, DeviceNet (hardware option required).
3. Meccanico & Specifiche ambientali

1. Maximum Permissible Motor-cable Length

Cavo non schermato: 200 M (with motor-reactor fitted).

Shielded cable: 100 M (with motor-reactor fitted).

R1 version (built-in A1-EMC filter): Massimo. 50 m shielded cable.

R0 version (nessun filtro integrato): Massimo. 25 m shielded cable.

1. EMC & Standard di sicurezza

R1 variant: Complies with EN55011 Class A1 (industrial EMC filter). R0: No internal filter.

Approvazioni: UL, CE. No built-in Safe-Torque-Off (STO) (STO introduced on successor FC280).

VII. Model-code Breakdown (VLT2807 full-model string)

VLT2807 P T 4 B 20 S B R1 D B F12 A00 C1

P = Process; T = Three-phase; 4 = 380-480 V; B = Book-style; 20 = IP20

R1 = Built-in A1-EMC filter; R0 = No filter

D = No brake chopper; B = Built-in brake chopper

F12 = With LCP keypad; F00 = Without keypad

VIII. Reference Order Numbers

VLT2807PT4B20SBR1DBF12A00C1 (con filtro + pannello): 134H2368

VLT2807PT4B20STR0DBF00A00C1 (nessun filtro, no panel): 195N1013

1. Replacement-model Parameter Comparison

FC280 Midi Drive 0.75 kW, 380-480 V

Identical power rating; high terminal-hardware compatibility; STO safety-function integrated; standard RS485 Modbus. Direct hardware replacement for VLT2807.

Control Modes of Danfoss VLT2807

Parameter P100 (Configuration Mode) defines the high-level drive-operating mode. The underlying motor algorithm is fixed as open-loop V/F. Vector-control and field-oriented control are not supported.

1. Underlying Motor-control Algorithm
2. V/F ad anello aperto (Voltage-to-Frequency) controllare (only motor-control algorithm)

Selectable Constant-Torque (CT) / Variable-Torque (VT) via P101; custom V/F curve available.

Static AMA motor auto-adaptation is supported for motor-stator-voltage-drop compensation.

No encoder-based closed-loop speed-vector control; not for high-precision speed-regulation.

1. Four Operating-mode Settings of Parameter P100

✅ Practical field-usage: P100=0 Open-loop speed control and P100=3 Process-PID closed-loop control.

III. Reference-source & Command-source Options

1. Local panel control (LCP keypad)

Parameter 002=1 LOCAL

Start-stop, forward/reverse and frequency reference set via keypad buttons.

Used for commissioning and local manual operation of standalone units.

2. External-terminal remote control (Parameter 002=0 REMOTE)

① Analogue-reference speed setting

Terminal 53: 0-10 V / 0-20 mA / 4-20 mA; potentiometer-speed-setting.

Terminal 60: 4-20 mA current-input only.

Terminal 33 configurable as pulse-frequency reference, max. 67.6 kHz.

② Digital-terminal control

Multivelocità: Combinations of digital-input terminals, fino a 8 preset fixed-speed setpoints.

Start-stop and direction: Terminal 18 for start, Terminal 19 for reverse.

Jog-function, precision-stop, fault-reset, output-inhibit.

3. Fieldbus communication control
4. Native RS485 (Terminals 68/69): Modbus-RTU, Metasys-N2. PLC controls start-stop, speed-reference and parameter-access.
5. Optional expansion cards: Profibus-DP / DeviceNet for bus-based command & reference.
6. Mixed-source control

Command-source and reference-source may differ. Esempio: Terminals for start-stop while bus provides frequency-reference; or bus for start-stop with potentiometer-analogue reference.

1. Braking Modes
2. AC-braking: Low-frequency AC excitation for fast deceleration; nessun hardware aggiuntivo richiesto.
3. DC-injection braking: DC injection to lock motor-shaft during stop; configurable braking-time and braking-voltage level.
4. Brake-chopper + brake-resistor (-B model suffix): Energy-dissipation braking for high-inertia regenerative-load applications.
5. Start-stop Logic Types
6. Ramp-start-stop: Smooth speed-ramp-up / ramp-down following acceleration-deceleration times.
7. Flying-start: Detect and synchronise to already-rotating motor speed.
8. Precision-stop: Counter-based stop for conveyor-station positioning.
9. Free-coast stop; Fast-stop OFF3.
10. Unsupported Control Functions

❌ No vector control (no VVC-plus, no flux-vector).

❌ No encoder-based closed-loop speed-control (no hardware encoder-interface).

❌ No positioning or servo-position-control.

❌ No Safe-Torque-Off (STO).

Typical Application-configuration Examples

1. General fan / conveyor speed-regulation: P100=0 Open-loop speed; terminal-start-stop + potentiometer reference on Terminal 53.
2. Constant-pressure water-supply pump: P100=3 Process-PID closed-loop; 4-20 mA pressure-transmitter connected to Terminal 60.
3. PLC fieldbus control: P100=0 Open-loop speed; RS485 Modbus-RTU; start-stop and speed-reference fully via bus.