Easy-Start ES Instruction Manual
Operation
SECTION 3
3-2
Operation
There are primarily two basic modes of operation.
1.
Voltage Ramp
- The motor voltage is
increased linearly from an initial step voltage,
until it reaches full line voltage. This is done
by the use of the two adjustments, time and
initial step. The initial step adjustment is
used to get the motor turning upon a start
command.
At very low initial step voltage settings, the
motor may not begin to turn for several
seconds.
For true voltage time-ramp operation, the
current limit should be set to its maximum
value ie. 500%, in this manner the current
limit is only used as an over-ride feature and
provides a safeguard from overcurrent.
2.
Current Ramp
- This type of operation
provides a motor current profile that starts
with an initial step of current, and then ramps
up linearly to a level which can be set by the
current limit adjustment.
This type of operation is recommended for
most high inertia loads since the motor speed
generally responds better with a current ramp
than it does with a voltage ramp.
In both the above modes of operation, the current
limit remains in the circuit to over-ride the ramp.
The current limit is adjustable from 200 to 500%.
A precaution must be advised here, that if the
current limit is adjusted too low, the motor may
start to rotate, but never reach rated speed. This
may cause the electronic current over-load to trip;
see Figure 3-1.
Adjustments
1.
Current Calibration DIP Switches (DS1,
DS2) work together as follows:
DS1 is active all the time.
DS2 is only in the
circuit whenever a connection is made
between TB1-2 and TB1-8 on the main
logic board
. If a relay is used, it should have
dry contacts. If this connection is not made,
DS2 reverts to Ò000Ó setting, and therefore
we use only the DS1 settings and the 1st
column of multipliers from 0.282 to 1.00; (see
Table 3-1). When a connection is made
between TB1-2 and TB1-8, this gives us 128
possible settings and extends the current
range to approximately 7:1.
The DIP switch current settings depend on
the CT used with the starter. The maximum
ampere setting is 1/6 of the CT rating.
Easy-Start ES Models and
CT Ratings
MODEL NO.
RATING AMPS
CT
ES045-E
45
270:1
ES070-E
70
420:1
ES120-E
120
720:1
ES180-N
180
1080:1
ES250-E
250
1500:1
ES260-N
260
1560:1
ES360
360
2160:1
ES500
500
3000:1
ES560-N
560
3360:1
ES750-N
750
4500:1
ES950-N
950
5700:1
Examples: (Using NEMA-12 Model ES250)
Example - 1
200 HP 235 FLA: To find the
multiplier divide 235/250=0.940
From tables use multiplier that is
equal or slightly less than 0.940
(use 0.934 DS1=Ò1101Ó
DS2=Ò000Ó) this gives us
0.934 x 250 = 234 amps.
Example - 2
100 HP 117 FLA: Multiplier =
117/250 = 0.468 (we select 0.460
DS1=Ò1001Ó and DS2=Ò111Ó) this
gives us 0.460 x 250=115 amps.
In order to activate DS2, connect
TB1-2 to TB1-8 on the logic board.
DIP Switch Code: OPEN = 0
CLOSED = 1
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