Although 20 amps is an absolute limit, the PS-PRO II will allow you to come as close as possible to using the full 20 amps, because with power sequencing, the risk of tripping the breaker is greatly reduced. The PS-PRO
IIhandles large but temporary inrush currents in stages, rather than simultaneously, allowing each stage to settle to its steady-state current draw before the next stage is powered.
Outlets and Plugs: The PS-PRO II’s four rear panel outlet pairs are standard 120V, 20A duplex types. These outlets are widely spaced, to ac- commodate one bulky plug-mounted “wall wart” power supply in each without covering up an adjacent outlet. The front panel outlet is limited to 15 amp use. The PS-PRO II also uses a 20 amp line cord, identified by the perpendicular blades on the plug. In 20 amp products, use of a plug of this type is required for UL safety certification. It is compatible with 20 amp outlets (such as those on the rear panel of the PS-PRO II). For more information about 20 amp plugs, see the information sheet “What Kind Of Plug Is This, Anyway?” accompanying this manual, or request a copy from Furman.
POWER
SEQUENCING
FEATURES
The PS-PRO II rear panel provides one un- switched and three switched outlet pairs. The switched outlet pairs are labeled Delay 1, Delay 2, and Delay 3. (The other pair of outlets on the rear panel and an additional single outlet on the front panel are unswitched.)
Here’s how the PS-PRO II works: When an ON sequence is initiated, power is immediately applied to the Delay 1 outlets. Power is then applied to Delay 2 and Delay 3 outlets per the 1-60 second total delay setting selected with the
front panel Delay Adjust control.
The Delay Adjust control, which can be set us- ing a screwdriver, controls the total delay time between Delay 2 and Delay 3. For example, if the Delay Adjust is set for 30 seconds, the De- lay 1 outlets will go on immediately, Delay 2 will power 15 seconds later and Delay 3 will power 15 seconds after Delay 2, for a total delay time of 30 seconds.
The order is reversed for the OFF sequence. For example, when an OFF sequence is initiated and the Delay Adjust control is set at 60 seconds, Delay 3 outlets lose power immediately, Delay 2 outlets lose power 30 seconds later and Delay 1 outlets lose power 30 seconds after Delay 2. The total delay time is 60 seconds.
In the event of a power outage, of course all equipment plugged into a PS-PRO II will lose power simultaneously. However, when power is restored, the delayed outlet groups will again turn on in the usual delayed sequence (if set to maintained on mode).
ON or off sequencing
The method of initiating an ON or OFF sequence depends on whether the unit is to be controlled locally or remotely. If remotely, it further depends on the type of switch or switches used (momentary or maintained).
local control
For local control, an ON sequence is initiated by turning the key switch to the ON position, and an OFF sequence by turning the key switch to OFF position. The START ON-OFF SEQUENCE pushbutton is not normally used in local operation.
NOTE: If the PS-PRO II is to be used under
