Hitachi Sj7002 Owners Manual

Using Intelligent Output Terminals
Operations
and Monitoring
4–60
Low Output 
Current Signal   The inverter monitors the output current to  the motor according to parameter C038, Low 
Current Indication Output M ode Select. Use parameter C039, Low Current Indication 
Detection Level, to set the low-current threshol d. The Low Output Current Signal [LOC] will 
turn ON if the output current is less than  the C038 threshold and motor operation corresponds 
to the selected monitoring mode.
Note 1: Note that...

SJ7002 Inverter
Operations
and Monitoring
4–61
Inverter Ready 
Signal   The inverter turns ON the Inverter Ready Signal [I RDY] output when it is ready to receive an 
operation command such as Run Forward, Run Reverse, or Jog. Otherwise, [IRDY] will be 
OFF and the inverter cannot accept operation  commands. If [IRDY] is OFF, then check the 
input power supply voltage at the [R], [S], and [T] terminals to be sure the voltage is within the 
input specification range. The [IRDY] output is  OFF when the...

Using Intelligent Output Terminals
Operations
and Monitoring
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Window 
Comparator 
Signals   The window comparator function outputs turn  ON when You can also monitor each analog 
input by comparing it to a thre shold value. This feature allows  the inverter to detect discon-
nected signal wiring, loss of power at a signal tr ansmitter, etc. When the input is below the set 
threshold value, the inverter substitutes the thre shold value for the input. The related parameters 
are given in the following...

SJ7002 Inverter
Operations
and Monitoring
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Analog Input Operation
Input Terminal 
SignalsSJ7002 inverters provide for an external analog 
input to command the inverter frequency output 
value. The analog input terminal group includes 
the [L], [OI], [O], [O2], and [H] terminals on the 
control connector, which provide for Voltage [O] 
and [O2] or Current [OI]  input. All analog input 
signals must use the analog ground [L].
If you use either the voltage or current analog 
input, you must select on e...

Analog Input Operation
Operations
and Monitoring
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The following tables show the available anal og input settings. Parameters A006, A005, and 
input terminal [AT] determine  the External Frequency Command input terminals that are avail-
able and how they function. The Trim Freque ncy input [O2]—[L] is available (when check 
marked) for some settings. Other settings make  the reverse direction (in addition to forward) 
available for bipolar input sett ings (when check marked). A bi polar input responds...

SJ7002 Inverter
Operations
and Monitoring
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The examples below show how the use of the [AT] input during operation enables/disables the 
Trim Frequency Command input [O2]—[L]. The [O2] —[L] input may be used alone, or as an 
offset control for the primary analog input.
Wiring ExamplesUsing an external potentiom eter is a common way to 
control the inverter output frequency (and a good way 
to learn how to use the analog inputs). The potentiome-
ter uses the built-in 10V reference [H] and the analog...

Analog Output Operation
Operations
and Monitoring
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Analog Output Operation
In the system design for inverter applications it  is sometimes useful to monitor inverter opera-
tion from a remote location. In some cases, this requires only a pane l-mounted analog meter 
(moving-coil type). In other  cases, a controller device such as a PLC may monitor and 
command the inverter frequency and other function s. The inverter can transmit the (real-time) 
output frequency, current, torque, or other para...

SJ7002 Inverter
Operations
and Monitoring
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To calibrate the meter reading, generate a full-s cale output (always ON) at terminal [FM]. Then 
use parameter B081(gain setting from 0 to 255) to  adjust the corresponding full-scale reading 
of the meter. For example, when the inverter  output frequency is 60 Hz, change the value of 
B081 so that the meter reads 60 Hz.
TIP:  When using the analog meter fo r monitoring, adjust the meter so it has a zero reading 
when the [FM] output is zero. Then use scale...

Analog Output Operation
Operations
and Monitoring
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[AM] and [AMI] 
TerminalsThe [AM] and [AMI] terminals provide signals 
to monitor various invert er parameters such as 
output frequency, output current, and torque. 
The terminals provide these analog signal types:
 [AM] terminal: 0–10V analog output signal
 [AMI] terminal: 4–20mA analog output 
signal
These signals both use the [L] terminal for signal 
return. Eight different inverter parameters may 
be monitored independently at either the [AM]...

SJ7002 Inverter
Operations
and Monitoring
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Setting Motor Constants for Vector Control
IntroductionThese advanced torque control algorithms impr ove performance, particularly at low speeds:
 Sensorless Vector Control –  improved torque control at outp ut frequencies down to 0.5 Hz. 
Use A044=03 (1st motor) or A244=03 (2nd mo tor) to select sensorless vector control.
 Sensorless Vector Control, 0Hz Domain –  improved torque control at output frequencies 
from 0 to 2.5 Hz. Use A044=04 (1st motor) or...