SAF OPAL Pro MS6 - Manual (Page 21)

MS6 REDUCED VOLTAGE STARTER
Page 20
7 FEATURES
7.1 SOFT STOP
• This provides a controlled stopping method to eliminate the water hammering effect
associated with fluid pumping applications.
• The Opal Pro operates in the opposite fashion of starting. When stop is initiated the Opal
Pro output voltage is reduced to the point set by parameter 1102 and then ramps down
based on a rate set in parameter 1103. The Opal Pro will remain on for the amount of time
set in parameter 1103. If two wire control is used then terminal 4 is a soft stop enable input
and when de-activated will turn the Opal Pro off during a soft stop.
7.2 SCR BY-PASS
• A three pole contactor used in conjunction with the by-pass contact eliminates the SCR
losses by shorting them out after the motor has reached full speed. This feature is a true
Watt Saver modification and permits the use of the Opal Pro in a NEMA 4 or NEMA 12
enclosure. The by-pass contactor is switched on only after the motor has reached full
speed and as such sees only motor full load current. At stop, the by-pass contactor is
opened while the SCR's are triggered fully on, limiting the power contacts opening voltage.
The SCR's are then switched off without having any voltage surge.
• When a by-pass contactor is used in conjunction with reversing, the REV contact must be
used to drive a slave relay that inter-locks the two by-pass contactors to ensure proper
sequencing of the contactors.
• This option requires by-pass lugs which are an add on option to the standard Opal Pro
7.3 SHEAR PIN PROTECTION
• This feature has been designed to provide motor jam protection, similar to a mechanical
shear pin.
• Once the motor has reached full speed, the MicroOpal will trip if the motor current
increases to 300%. Parameter 1501 enables or disables this feature.
7.4 SLOW SPEED FWD/REV (JOG)
• This provides the ability to run an AC motor at 14% speed in the forward direction or 20%
in the reverse direction without any added SCR’s.
• To jog in the forward direction the jog input (terminal 5) must be activated
• To jog in the reverse direction the jog input (terminal 5) and the rev input (terminal 6) must
be activated.
• Current draw is abnormally high during jog mode therefore it must only be used for very
short amount of time to avoid overload trips and excessive motor heating.