The new ELCA Current Rectifier DIGITAL type All Functions Programming SCR firing control and output regulation Parameter and Alarm Indication Interfacing with external PC or PLC are controlled by a fully digital system For PULSE Rectifier: - Working with positive Pulses
ISO9001:2000 Certified

ADVANTAGES IN USING PULSE RECTIFIES IN ANODIZING

Even if the working is carried out with the same average current value, the oxide quality is better than the one obtained by using a conventional rectifier; as proved by the tests on abrasion, efficiency (ISO 3210) and corrosion (Kesternich).  It is also possible (without disvantages) to anodize by using a current density higher than with conventional rectifiers. Thus the use of pulse rectifiers gives the benefits of 20-25% time saving compared with the conventional ones.

 

CHOICE OF PULSE RECTIFIER RATED CURRENT VALUE (Ampere)

Pulse rectifiers are characterized by the following 3 parameters: Base current (rated current value) Pulse current = base current x 1.5 Average current = 1.35 x base current Therfore the following advantages can be obtained: better oxide quality (but without any time saving) if the Average current of the pulse rectifier is the same as the conventional rectifier rated current better oxide quality and time saving (up to 20-25%) if the BASE current of the pulse rectifier is the same as the conventional rectifier rated current

Example: Base current = 6.000 Adc Pulse current = 6.000 x 1.5 = 9.000 Adc Average current = Base x 1.35 = 6.000 x 1.35 = 8.100 Adc

 

MAIN TECHNICAL FEATURES Continuous duty Electronic control, 0 to 100%, by means of SCRs on primary or secondary side Main transformer according to "Safety isolating transformers" standard 6 pulse rectifier power cicuit Constant voltage and (or) constant current control (Selectable) Accurancy: ±1% of f.s. value for load variation from 10% to 100% Cooling: Forced air (Protection degree IP20) or alternatively: Mixed air / water (Protection degree IP20) Water cooling (Protection degree IP54) Automatic main breaker provided Max. current, Max. temperature protections Remote control panel Standard reference: EN 60146 (IEC 146)

 

OPTIONAL: Interfacing with external PLC Analogue signals (by means of opto-insulated cards) and contacts FIELDBUS interface (by means of serial line) APC Anodizing Process Computer (New type) that allows: Automatic survey of the surface to be anodized Presetting of anodizing current density and requested number of microns Automatic carring out of the anodizing process, setting the current density (A/sqdm.) and the requested micron number only. Automatic printout of anodizing parameters Clik on the image to enlarge The APC calculates automatically the load surface and controls directly the output of the rectifier; a cycle-end alarm is operated at the end of the process. The APC can also be equipped with printer, for the automatic printout of process parameters.

NOTE: Due to technical reasons existing rectifiers can't be equipped with APC device

Choice of anodizing rectifiers control facility:

MANUAL CONTROL (always provided)	Start/Stop by means of proper buttons Output voltage (current) adjustment by means of potentiometer knob(s) on the control panel Anodizing time adjustable by means of timer on the control panel.
AUTOMATIC CONTROL by means of APC (provided on request)	Start/Stop by means of proper buttons Current density (A/dm2) and thickness (micron) presetting on APC keyboard. The rectifier delivers automatically the requested current. When the preset micron number is got an acoustic-visual signal operates. Automatic printout of treatment parameters when stop button is pressed.
INTERFACING WITH EXTERNAL PLC (provided on request) ONE OF THE FOLLOWING TWO WAYS CAN BE CHOSEN: By means of analogue signals (opto insulated cards provided) and contacts FIELDBUS interface (serial line).	Analogue signals and contacts: Start/Stop according to external contact (the rectifier works while the contact is closed). Voltage (current) adjustment by means of analogue signal* (4-20mA) or (0-10V). Feedback signals* proportional to output voltage and current Anodizing time by means of external PLC contact. * (by means of opto insulated cards) FIELDBUS interface (serial line): This system allows to control the start/stop, the supplied voltage (current) adjustment, to read back the signals proportional to output voltage and current and the rectifier status by means of digital commands via the serial line
AUTOMATIC CONTROL by means of APC AND EXTERNAL PLC (provided on request)	Start/stop by means of external contact (the rectifier works while the contact is closed). Output current adjustment carried out by APC on the base of measured surface and pre-set current density. Anodizing time calculated by APC; cycle-end contact available for external PLC when the pre-set micron number has been reached. Printout of process parameters at Stop. The exchange of parameters and digital information via serial line is also possible.