Features

    *16-40 amps, 200-500 Vac 

    *Zero cross or phase angle firing 

    *Optional current limit

    *Optional Load Fault Alarms

    *Optional Modbus® communications 
The Model 7300A is a new range of economic SCR Power Controllers for use with resistive, infrared or inductive loads. This unit features integral heatsinks with analog voltage or current inputs for precise control. Options include Gross Fault (GRF) Detection, Diagnostic Load Failure (DLF) Detection, Current Limit and digital communications. GRF indicates when a shorted device or an open load is detected. Similar to GRF, DLF detects a shorted device, an open load and partial load failure. Current limit is available for use with variable resistance loads and digital communications is available for remote control or monitoring of the process.
TECHNICAL SPECIFICATIONS

 
Power
Nominal Current 16A to 630A per phase at 45°C
Nominal Voltage 200 V to 690 V
Frequency Use from 47 to 63 Hz
Dissipated Power  1.3 W (approx.) per amp and per phase
Cooling Rating < 63 A: Natural convection
Rating > 80 A: Fan-cooled
115 V or 230 V fan; consumption 10 VA
Load Three-phase industrial load.
Use category • AC-51 Resistive load with low temperature coefficient.
• AC-55b Short wave infrared elements

• AC-56a Transformer primary and Resistive load with high temperature coefficient.
 
Control
Supply Self-powered from supply network, or external (115 V or 230 V +10%; -15%)
Consumption: 10 VA.
Control type Analogue (optional digital communication)
• Remote analogue setpoint:
0-5 V or 0-10 V (100 kW . input),
0-20 mA or 4-20 mA (250 W input)
• Potentiometer for manual setpoint
(5 V supply available).
 
Firing mode    
Firing at zero crossings • ‘Burst mode’
base time: 16 or 64 cycles
• ‘Single cycle’: base time 1 cycle
• ‘Advanced single-cycle’:
base firing time 1 cycle;
non firing by half-cycles.
Firing angle variation • Phase angle
 
Control
Control parameter • Standard:
- load voltage squared (V2)
• Option:
- - apparent power (V × I)
- - load current squared (I2)
- - open loop.
Linearity and Stability Better than ±2% of full scale
(balanced supply and load).
Current limit Option, depending on firing mode:
• ‘Phase angle’:
Automatic control transfer
- from V2 to I2 or
- from V × I to I2
with current recalibration set by potentiometer on front panel.
• Burst mode, 16 cycle base:
Current limited by threshold set using potentiometer on front panel.
Calibration A control signal is available in V × I for power and current calibration and maintenance.
Transient current limit Option for transformer primary control in ‘burst mode’ firing:
• Transformer magnetisation firing angle ramp at first switch on.
• First firing delay adjustable using potentiometer on front panel.
   
Signalling Electronics supply present:
green ‘ON’ LED.
Thyristor firing request:
green ‘HEAT’ LED.
 
Type 1 alarms (Options)
Serious alarms Total load failure and thyristor short
(GRF option) circuit detection.
Signalled by red ‘GRF’ LED and alarm relay contact.
Diagnostic alarm Partial load failure detection.
(DLF option) Signalled by orange ‘DLF’ LED and alarm relay contact.
Settings: Monitoring diagnosis, alarm adjustment and resetting using push button on front panel.
Sensitivity: Detects the failure of at least one heating element for six identical elements connected in parallel.
The DLF option includes serious alarm monitoring (GRF).
Over-temperature alarm For all fan-cooled units (> 80 A) operation stops if the temperature threshold is exceeded.
Signalled by red ‘T°’ LED and alarm relay (if GRF or DLF option selected).
   
Type 2 alarm (Option)
Over-current alarm Operation stopped if current threshold
(ICO option) exceeded.
Only available with zero crossing firing and DLF option (except for short wave infrared elements, transformers and codes VICL and V2CL).
Alarm threshold adjustable from 20 to 100% using potentiometer on front panel.
Signalled by red ‘ICO’ LED and alarm relay contact.
   
Alarm relay Available with alarm options.
The relay contact (0.25 A/230 Vac; 32Vdc) is either open on alarm or closed on alarm depending on the product code.
   
Communication Available later.
   
Protection
Thyristor protection Varistor and RC snubber.
Short circuit Coordination type : Type 1.
High speed fuses :
. rating < 100 A: external (optional)
. rating > 125 A: internal.
No fuse for short wave infrared elements in firing at zero crossings or in phase angle firing mode without current limit.
Electrical protection IP20 without adding additional protection.
Overvoltage category 3 (defined by IEC 664).
   
Product standard The 7300A products comply with the terms of product standard EN 60947-4-3
‘Contactors and motor-starters -
AC semiconductor controllers and contactors for non-motor loads’.
   
CE labelling Complies with the essential requirements of the European Low Voltage Directive 73/23 EEC dated 19 February 1973, modified by 93/68/EEC dated 22 July 1993 and the Electromagnetic Compatibility Directive 89/336/EEC dated 3 May 1989 modified by 92/31/EEC dated 28 April 1992 and 93/68/EEC dated 22/07/93.
   
Environment
Use 0 to 45°C with nominal current,
at max. altitude of 2000 m.
Storage -10°C to 70°C.
Pollution Degree 2 acceptable (defined by CEI 664).
Humidity RH 5% to 95% non-condensing.
   
Dimensions Rating 16 A to 40 A:
H × W × D (overall) Basic version: 220 × 96 × 215 mm
Options: 220 × 96 × 243 mm.
Weight Maximum 2.5 kg.