The initial-torque and kick-start settings on a solid-state soft starter deal with a specific problem: a smooth, gentle ramp does not always produce enough torque at the very start to get a sticky or high-friction load moving. The initial-torque setting, sometimes called the pedestal, raises the voltage the ramp begins from so the motor starts with useful torque instead of climbing from near zero. The kick-start setting goes further, applying a brief burst of high voltage for a fraction of a second at the very beginning to jolt a stubborn load into motion, after which the normal ramp takes over. This page explains when these settings are needed, how to think about them for loads like conveyors and sludge pumps, and how they appear in the current trace.
Kick-Start / Initial Torque in one line: The initial-torque (pedestal) setting on a soft starter sets the voltage the ramp begins from, so the motor starts with enough torque to move the load rather than ramping up from near zero. The kick-start setting adds a brief pulse of high voltage, lasting a fraction of a second, at the very start to break away a sticky or high-friction load before the normal ramp begins. Both are used when a smooth ramp alone cannot develop the breakaway torque a stubborn load needs, such as a loaded conveyor or a settled sludge pump.
A soft starter's basic job is to raise the motor voltage smoothly from a low starting point, easing the motor and load into motion instead of slamming them with full voltage. The catch is that torque follows roughly the square of voltage, so at the low end of the ramp the motor produces very little torque. For a load that starts freely this is fine, but for a load that resists starting, one with high static friction, a settled or compacted material, or a mechanical stiction that has to be overcome, the motor may sit there developing a gentle, rising torque that is simply not enough to break the load loose. The motor hums, draws current, and does not turn.
This is where the smoothness of the soft start works against it. The very gentleness that protects the drivetrain from a violent start also means the motor spends the first part of the ramp too weak to move a stubborn load. Left alone, the load never breaks away, the motor never accelerates, and the start eventually trips on excess start time. The load types that provoke this are recognizable: long or heavily loaded conveyors that have to overcome the friction of a full belt, sludge and slurry pumps whose settled solids resist the first turn, and machines that have sat idle and stiffened.
The initial-torque and kick-start settings exist precisely to give the motor more muscle at the moment of breakaway without abandoning the smooth ramp for the rest of the start. They are not about the whole start profile; they are about the first instant, getting the load moving, after which the normal ramp can carry it up to speed gently. Choosing them is a matter of adding just enough breakaway boost to reliably start the load and no more, so the benefit of the soft start is preserved for the acceleration that follows.
The initial-torque setting, often called the initial voltage or pedestal, raises the point the ramp starts from. Instead of beginning the ramp near zero voltage, the starter begins at an elevated voltage that already produces useful torque, then ramps up from there. This gives the motor meaningful torque from the first instant and is the gentler of the two boosts, suited to loads that need a firmer start than a low pedestal provides but do not need a violent jolt. Setting the pedestal too high, though, sacrifices smoothness, because a high starting voltage means a more abrupt initial torque, so it is set just high enough to reliably start the load.
The kick-start is a more forceful tool. It applies a brief pulse of high voltage, typically for a fraction of a second, at the very beginning of the start, producing a short burst of high torque to jolt a stuck load into motion, after which the voltage drops back to the normal ramp. The kick-start is defined by two things: how high the pulse goes and how long it lasts. It is meant to be short, just long enough to break the load loose, because it is essentially a brief, controlled shove that gives up the soft start's smoothness for that instant in exchange for the breakaway torque a pedestal alone cannot supply.
The two are chosen by how stubborn the load is. A load that needs a bit more torque from the start is handled with an initial-torque pedestal; a load that genuinely resists breaking away, where even an elevated pedestal is not enough to overcome the stiction, gets a kick-start pulse. Both should be tuned conservatively, applying the least boost that reliably starts the load, because both trade away some of the gentleness that is the reason for using a soft starter in the first place. Over-applying a kick-start negates much of the mechanical benefit and can jolt the drivetrain nearly as hard as a direct start.
A kick-start leaves a clear mark on the current trace: a brief, sharp spike of current at the very start, corresponding to the high-voltage pulse, followed by the current dropping to the normal ramp profile once the pulse ends and the load has begun to move. An initial-torque pedestal shows more subtly, as a start that begins from an elevated current rather than climbing from a low value. Reading these features tells an observer not just that a soft start happened, but that a breakaway boost was applied and, from the shape, whether it was a pedestal or a pulse.
The trace also reveals whether the boost is doing its job. If the current spikes for the kick-start pulse and the motor then accelerates smoothly, the breakaway succeeded. If the current spikes, the pulse ends, and the current stays elevated without the motor accelerating, the boost was not enough to break the load loose and the start is heading for a stall. Watching the current behavior immediately after the boost is how a maintainer judges whether the kick-start or pedestal is correctly set for the load as it currently is, which matters because loads change: a conveyor accumulates material, a sludge pump's solids settle harder over an idle period.
For remote and unmanned sites, cloud SCADA that captures the start current profile makes this diagnosis possible without a visit. An operator seeing that a sludge pump now needs several kick-start attempts to break away, or that the current lingers elevated after the boost before the pump finally starts, has early evidence that the load is getting stickier and the start settings, or the mechanical condition, need attention. Trending across a fleet flags the machine whose breakaway is becoming marginal, so someone can adjust the initial-torque or kick-start setting, or investigate the load, before the start begins failing outright at a site nobody attends.
Initial torque, or the pedestal, raises the voltage the ramp starts from so the motor begins with useful torque instead of climbing from near zero, giving a firmer but still relatively smooth start. Kick-start applies a brief pulse of high voltage, lasting a fraction of a second, to jolt a genuinely stuck load loose before the normal ramp begins. The pedestal is the gentler boost for loads needing a firmer start; the kick-start is the forceful shove for loads that resist breaking away.
You need a kick-start when a load resists breaking away and even an elevated initial-torque pedestal cannot develop enough torque to get it moving on the smooth ramp. Typical cases are long or heavily loaded conveyors, sludge and slurry pumps whose settled solids resist the first turn, and machines that have sat idle and stiffened. If a soft start repeatedly stalls or trips on excess start time because the load will not break loose, a kick-start pulse is the setting that addresses it.
Only if it is over-applied. A brief, minimal kick-start jolts the load loose for a fraction of a second and then hands off to the smooth ramp, so the gentle acceleration that protects the drivetrain is preserved for the bulk of the start. But setting the kick-start too high or too long jolts the drivetrain nearly as hard as a direct start, negating much of the mechanical benefit, so it should be tuned to the least boost that reliably breaks the load away.
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