Phasetronics
Page 11
Chapter 5 - Options
5.1 Power-on Soft Start (Standard)
This option is ideal for high inrush loads & delicate heater elements. The gradual ramp to the command
level eliminates inrush and prevents thermal shock. Here is how it works. When unit power is applied and
a Manual or Automatic command signal is present the unit will ramp the output voltage to the commanded
level. The ramp time is adjustable via potentiometer P3 on the main (mother) board. The 0-100% output
voltage ramp interval can be adjusted from a minimum of 0.5 seconds with P3 set fully counter clockwise,
to a maximum of 20 seconds with P3 set fully clockwise. This option can be disabled by removing X6
(PCL1002) or X7 (EPCL1001) on the mainboard. (See illustrations 7.1 or 7.2 for jumper location.)
Note:
The overall ramp time is determined by the command level. For example; If the soft start time is set
to 20 seconds and the command level is 50%, the total ramp time to the command level will be 10
seconds
.
5.2 Current Limit (Option "C")
The Current Limit option provides an additional layer of protection for dynamic and non-linear loads.
Adjustable from 0-110% of the units rating, this option will override the control signal to limit the output
current to a predetermined level. By adjusting the P4 potentiometer on the option card, the level can be
set to zero at the fully counter clockwise position to 110% of the units rating when at the fully clockwise
position. This feature is useful when the load can vary during process transitions or during a start-up
condition. This option can also be disabled by removing the X4 jumper on the option card. (See
illustrations 7.3 or 7.4 for jumper location.)
5.3
Load Voltage Regulation (Option “R”)
Load Voltage Regulation provides a means of stabilizing the output voltage when input voltage variations
are present. The unit monitors its output voltage thru the onboard feedback loop and compares it to the
command signal to provide regulation.
Output regulation of +/-2% over a +/-10% input voltage swing can be beneficial in heating or other critical
applications where stability and repeatability is of concern. This feature is factory set using the P1
potentiometer on the option card. Adjusting the P1 potentiometer should be avoided as it will affect the
units output voltage scaling and regulation.
5.4 Command Signal Change Soft Start (Option "S")
This option provides a soft start on Command signal Change, Current Trip Reset or when Lockout is
released. It protects fuses from inrush currents and is well suited for high inrush loads and delicate heater
elements. When power is applied and the command signal is brought to zero (0%) for more than 1
second, the unit resets its soft start circuitry and will ramp its output voltage when the commend signal is
increased to any value from zero. The ramp rate is adjusted by the P2 potentiometer on the option card.
When set at minimum (fully counter clockwise) the ramp time is ~0.75 seconds to 100% output. When set
at max (fully clockwise) the ramp time is ~12 seconds. This option can also be disabled by removing the
X2 jumper on the option card. (See illustration 7.3 or 7.4 for the jumper location.)
