Mitsubishi Electric FR-A800, Instruction Manual

Page: 477 / 1042

Parameters (H) Protective function parameter
FR-A800 5 - 297
Motor permissible load level setting (Pr. 607, Pr. 608)
The electronic thermal O/L relay operation characteristic can be changed by setting the permissible
load level according to the motor characteristics.
Electronic thermal O/L relay pre-alarm (TH) and warning signal (THP signal)
●
If the accumulated electronic thermal value reaches 85% of the Pr. 9 or Pr. 51 setting, electronic
thermal O/L relay function pre-alarm (TH) is displayed and the electronic thermal O/L relay pre-
alarm (THP) signal is output. If the value reaches 100% of the Pr. 9 setting, the motor thermal
protection (E.THM/E.THT) is activated to shut off the inverter output. The inverter output is not
shut off with the TH display.
●
The inverter output is not shut off with the warning signal (THP).
●
For the terminal used for THP signal output, set "8 (positive logic)" or "108 (negative logic)" in any
of Pr. 190 to Pr. 196 (output terminal function selection) to assign the function.
I002851E
Fig. 5-124: Example of motor permissible load setting (when Pr. 9 = "100% of the inverter rating")
I001138E
Fig. 5-125: Prealarm signal output
NOTE Changing the terminal assignment using Pr. 190 to Pr. 196 (output terminal function selection)
may affect the other functions. Set parameters after confirming the function of each terminal.
0
60
120
180
240
80 100 120 140 160 180 200
Inverter output power (%)
(% to the inverter rated current)
Range for the
transistor
protection
T
h
ermal r
e
la
y op
er
ation
time [s]
Motor permissible load 200%
Motor permissible load 150% (Initial value)
Motor permissible load
110%
Time
100 %: Electronic thermal O/L relay activation value
Electronic thermal
O/L relay alarm
(THP)
Electronic thermal
relay function
operation level
OFF ON ON