Operation time (minutes)
Cold start
Hot start
Motor current (%)
E2-01 = 100% m o t o r c u r r e n t
10
7
3
1
0.4
0.1
0
100
150
200
Figure 5.74 Motor Protection Operation Time
n
Motor Protection Using a Positive Temperature Coefficient (PTC)
A motor PTC can be connected to an analog input of the drive. This input is used by the drive for motor overheat protection.
When the motor overheat alarm level is reached, an oH3 alarm will be triggered and the drive will continue operation as
selected in L1-03. When the overheat fault level is reached an oH4 fault is triggered, a fault signal will be output and the
drive will stop the motor using the stop method determined in L1-04.
Figure 5.75
shows a PTC connection example for analog input A2. If using analog input A2, make sure to set DIP switch
S1 on the terminal board for voltage input when using this function.
Drive
+V
(+10.5V, 20 mA)
Multi-function input
Branch
resistor
12 k
PTC
thermistor
MA
Multi-function
output (contact)
Multi-function
output (photocoupler)
MB
MC
P1
P2
PC
A2 (0-10 V)
AC
Figure 5.75 Connection of a Motor PTC
The PTC must have the following characteristics for one motor phase. Normally a motor is protected by three PTCs
connected in series.
Tr’
Figure 5.76 Motor PTC Characteristics
Overheat detection using a PTC can be set up by parameters L1-03/04/05 as explained below.
5.8 L: Protection Functions
SIEP C710606 20 OYMC AC Drive - V1000 User Manual
187
5
Parameter Details
7/16/2008-13:23