Mitsubishi Electronics FR-A720-0.4k to 90k Marine Battery User Manual


 
185
Selection and protection of a motor
4
PARAMETERS
(3) Set multiple electronic thermal relay functions (Pr. 51)
(4) Electronic thermal relay function pre-alarm (TH) and alarm signal (THP signal)
Use this function when rotating two motors of different rated currents individually by a
single inverter. (When rotating two motors together, use external thermal relays.)
Set the rated current of the second motor in Pr. 51.
When the RT signal is ON, thermal protection is provided based on the Pr. 51 setting.
REMARKS
The RT signal acts as the second function selection signal and makes the other second functions valid. (Refer to page 235)
The RT signal is assigned to the RT terminal in the initial setting. By setting "3" in any of Pr. 178 to Pr. 189 (input terminal function
selection), you can assign the RT signal to the other terminal.
100%: Electronic thermal relay function alarm operation value
The alarm signal (THP) is output and an electronic thermal pre-
alarm (TH) is displayed when the electronic thermal relay
function cumulative value reaches 85% of the level set in Pr. 9
or Pr. 51. If it reaches 100% of the Pr. 9 Electronic thermal O/L
relay setting, electronic thermal relay function protection (E.
THM/E.THT) occurs.
The inverter does not trip if the alarm signal is output.
For the terminal used for the THP signal output, assign the
function by setting "8" (positive logic) or "108" (negative logic) in
any of
Pr. 190 to Pr. 196 (output terminal function selection)
.
CAUTION
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.
.... Output current value is used to perform integration processing.
.... Output current is assumed as 0A to perform integration processing. (cooling processing)
× ..... Electronic thermal relay function is not activated.
Pr. 450
Second applied
motor
Pr. 9
Electronic thermal
O/L relay
Pr. 51
Second electronic thermal O/L
relay
RT = OFF RT = ON
First
motor
Second
motor
First
motor
Second
motor
9999 0
9999
××××
0 ××××
0.01 to 500 (0.1 to 3600)
× ×
9999
Other than
0
9999
× ×
0
× ×
0.01 to 500 (0.1 to 3600)

Other than
9999
0
9999
××××
0 ××××
0.01 to 500 (0.1 to 3600)
× ×
Other than
9999
Other than
0
9999

0
× ×
0.01 to 500 (0.1 to 3600)

RT
MC
MC
W
V
U
IM
IM
SD
OFF
ON
100%
85%
Time
ON
Electronic thermal
relay function
operation level
Electronic thermal O/L
relay alarm
(THP)