other units.
The STATUS lines work the same in either mode. Each reflects the true state of the unit’s outlets and is affected by both the “memorized” state and by the key lock switch. A separate LED must be used to indicate the status of each PS-PRO HT.
To address the unusual (hopefully rare) instance when several PS-PRO HTs in parallel fall out of sync, resulting in some units turning on and oth- ers turning off when a remote button is pushed, the remote signal line has a special feature: Holding the REM line high for at least 4 seconds will force all units to the OFF state, putting them back in sync. This is the only way to re-sync units other than disconnecting AC power to all units. Remember — turning any key lock switch to OFF does not affect the stored state, even though it will temporarily turn the output of that unit off. If it is turned back to REM, the PS-PRO HT will sequence back to ON because the stored state is still ON.
The above covers the case of multiple units in parallel (all sequences initiate simultaneously).
See “AC Relay Accessory PS-REL” below for a discussion of wiring multiple units in series.
STATUS Terminal
The STATUS terminal is an output that may be used to illuminate an LED at the remote location indicating that the power is available at the PS- PRO HT’s outlets. If it is high (+5V), the unit is ON (or at least in the process of sequencing ON); if low, the unit is OFF (or sequencing OFF). Simply connect the indicator LED between STATUS and ground (do not use a series resistor). If the LED does not light when the switch is in the ON position check the polarity and reverse the LED leads if needed.
Effects of Lightning
Lightning is a natural phenomenon of over- whelming force that represents the most dif- ficult circumstance faced by a power protection product. The degree of protection a PS-PRO HT can offer depends on the intensity of the strike. If lightning strikes a distant power line and causes a relatively small disturbance to reach your location, the spike suppressors in the PS-PRO HT will absorb the excess voltage invisibly and harmlessly. However, if lightning strikes the actual building where the PS-PRO HT is installed (or somewhere very nearby), some damage may be unavoidable due to the ex- tremely high voltage and current present. If this does occur, most likely damage will be limited to the PS-PRO HT itself and will affect only certain spike suppression components (called varistors or MOV’s.) In this “suicide” mode, the PS-PRO HT may sustain minor damage but generally will protect all equipment plugged into it from much more serious and costly damage as long as that equipment is properly grounded. Proper grounding requires the use of three-prong AC cords, and that the building’s outlets are actually grounded to earth as specified by the National Electrical Code.
Any PS-PRO HT known to have taken a direct lightning hit should be checked by a qualified technician or the Furman factory to determine of the MOV’s need replacement. (If the PS-PRO HT’s PROTECTION OK indicator is not lit, there is definitely some damage. Some spike suppres- sion capability may still be available by MOV Bank #2, but there is no guarantee of this.)
For optimum protection, you should not rely ex- clusively on the PS-PRO HT to protect against a direct lightning hit. The first line of defense against lightning should be a lightning arrestor installed on your building’s electrical service entrance. If your building does not have one, contact your local power company or an electri- cal contractor to have one installed.