Shimaden PAC18 Series, Инструкция по эксплуатации

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11-3. Variation limit (slow-up / slow-down) time adjustment
The variation limit function delays PAC18 output response relative to control input signal variation.
It is effective for suppressing transient current when power is turned on, etc., and controlling heater inrush current so as not to place a burden on power
equipment. Slow-up/slow-down time is the time required for output to go from 0 to 100%. Slow-up/slow-down time is set from 0.0 to 99.9 seconds
by key sequence ‘1-10. Variation Limit.’ Slow-up/slow-down time cannot be set separately.
The longer the time is set, the slower output response is. Adjust time according to characteristics of load used.
The factory setting is approximately 1 second. If time is set shorter than this, the overcurrent protection function may be triggered depending on load
conditions.
For setting change of key sequence ‘1-7. Ramp lower limit setting’ and key sequence ‘1-8. Ramp higher limit option,’ and when conducting ramp
adjustment by external adjuster, output cannot be changed by variation limit.
Operation diagram
Output
Slow-down
Approx.
3 seconds
Slow-up
Input
power
Power on
Control
input
25 ％
100 ％
0 ％
100 ％
75 ％
0 ％
100 ％
11-4. Current limit function (optional)
Function for limiting output current to within 0 – 120% of the device’s rated current. Limits current and protects the thyristor if using loads with large
inrush current such as pure metal heaters or lamp heaters.
Detects output current by built-in CT and produces delay time to control the control angle of the thyristor (response time 0.1 sec. or less).
Sudden change in load while conducting power therefore may not be handled.
If using external current limit setting B characteristic 10k
Ω (VR), allocate by key sequence ‘1-11. Current limiter.’
(If allocating to VR, current limit is 100% of rated current.)
For large inrush current load, use with variation limit (slow-up/slow-down) time set to at least 2 seconds.
6
5
4
R1
R3
R2
①
②
③
VR1
B10k Ω
4
6
7
R1
R3
L2
②
③
①
VR2
B10k
Ω
Allocation Terminal
block No.
Terminal
symbol
Adjuster No.
VR1
VR2
4
5
6
4
7
6
R1
R2
R3
R1
L2
R3
①
②
③
①
②
③
External adjuster terminal block layout
Also, if current exceeds 130% of the rated current, the circuit inside the device is triggered to force output to 0%.; alarm display  is displayed and the
data display displays

. (Standby display displayed for 0-0. Basic screen only) Remove the cause of the alarm and turn the power back on.
Note
・ The current limit function is not activated for cycle calculation zero voltage switching control or complex control.
・
The more load rate exceeds 100%, the more output power drops. (Limit current to set value by lowering output voltage.)
・ If current limit setting device is removed with external current limit setting device (VR) set to key sequence ‘1-11. Current limiter’ setting,
current is limited to 0% of rated current and there is no output.