User manual FURMAN AR1220

[. . . ] There are no controls except an on off breaker switch. (The AR-1220J also has an output voltage selector switch. ) Limitations: These Line Voltage Regul ators are for use with AC voltage only. DC voltages should never be applied to them. Also, they do not change or regulate line frequency. [. . . ] The output is also shut down for extremely low input voltages (those below 75V, or 65V in 100V mode). INPUT VOLTAGE MONITORING The row of ten LED's at the top left of the front panel make up a meter that indicates INPUT VOLTAGE. There are two red LED's at the endpoints. When lit, they indicate that the input voltage may be above or below the point where it can be restored to the selected nomi2 AR-1220 A C L I N E V O LTA G E R E G U L AT O R can have voltages as high as 6000 volts. Though they are usually of very short duration, the energy they contain can be considerable, enough to damage sensitive solid state components in audio and computer equipment. Spikes can also foul switch contacts and degrade wiring insulation. They are an unavoidable component of electric power. They are caused unpredictably by electric motors switching on or off (on the premises or outside), utility company maintenance operations, nearby lightning strikes, and other factors. Spikes (also called surges or transients) are absorbed by special components called MOV's in the AR series to provide safe voltage levels to protect your equipment. RF11EMI INTERFERENCE: Noise from RFI (Radio Frequency Interference) or EMI (Electro Magnetic Interference) involves lower voltages and less energy than is found in spikes, but it is continuous rather than transient in nature. It is not likely to cause physical damage, but it can certainly be annoying, producing static in audio circuits, "snow" on video screens, or garbled data in computers. Noise can be introduced into AC lines by nearby radio transmitters, certain kinds of lighting, electric motors, and others. Because noise occurs at higher frequencies than the 50 or 60 Hz AC line, it can be effectively reduced through use of low pass filtering. nal output voltage (though it may still be restored to a usable level) but is not high or low enough to cause an extreme voltage shutdown. The AR 1220J has switchable output voltages, and also has multiple scales on the Input Voltage meter corresponding to the selected voltage. OUTPUT VOLTAGE MONITORING A green LED labelled OUTPUT IN REGULATION indicates proper function (i. e. , that the output voltage is within ±5V of the selected output voltage). Your equipment always will work normally when this light is on, and often will work satisfactorily even when the OUTPUT IN REGULATION LED is off. If you wish to monitor your AR-1220's output voltage more pre-cisely, you may want to use a Furman Sound PL PLUS Power Conditioner and Light Module in conjunction with it. The PL-PLUS is the perfect complement to a Furman Voltage Regulator to assist in rack power distribution. It offers a 20 LED bar graph line voltage meter to monitor the incoming line (the Voltage Regulator output), twin slide out, swiveling lights with a dimmer control for equipment illumination, and eight additional outlets with their own spike and surge protection and RFI filtering. DEFINITIONS VOLTAGE REGULATION. The AC line voltage is a number indicating the nominal electrical potential that has been adopted in a region for powering electrical equipment of all kinds. In most of North America it is 117 120 volts AC; in Japan, 100 volts; and in many other countries 220, 230, or 240 volts. The actual voltage can fall below or rise above this nominal level due to brownouts, power cutbacks, use of substandard wiring, and other causes. These deviations can cause poor performance or malfunction. A regulator is a device which, through use of a transformer, corrects the voltage deviation by stepping it up or down so that it is as close as possible to the nominal level. [. . . ] If any part of this Limited Warranty is determined to be void or illegal, the remainder shall remain in full force and effect. The AR 1220 uses a design based on an eight tap toroidal autoformer. The toroidal design assures minimal leakage of stray magnetic fields, and, because of its high efficiency, a very com-pact size for its rating. The Voltage Regulator's circuitry monitors the incoming line voltage with each cycle, comparing it to ar extremely precise voltage reference, accurate to ±0. 15%. If a voltage e fluctuation requires that a different tap be selected, the new tap is electronically switched exactly at the zero crossing, to avoid distorting the AC waveform. [. . . ]