WEG CFW-11 Installation And Operation Manual - page 10
Safety Stop Function
10 | CFW-11, CFW-11M, CFW70X
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3. OPERATION
3.1 TRUTH TABLE
Table 3: Safety stop function operation
STO1 logic level
(voltage between
XC25:1-3
terminals)
STO2 logic level
(voltage between
XC25:2-4
terminals)
Safety stop
function
Inverter behavior
0 (0 V)
0 (0 V)
Activated
(enabled)
Inverter remains in STO state and does not
accept commands. In CFW70x inverters with
software version V1.02 or higher, it’s indicated
A170 (activation of safety stop function advice)
on the keypad. In order to escape this condition,
it’s required to have STO1 = 1 and STO2 = 1
simultaneously.
0 (0 V)
1 (24 V)
Fault
Inverter is tripped by F160 fault (safety stop
function related fault). To escape this condition,
it’s required to reset the inverter.
1 (24 V)
0 (0 V)
1 (24 V)
1 (24 V)
Disabled
Inverter accepts commands normally.
NOTE!
Maximum delay between STO1 and STO2 signals: 100 ms (otherwise inverter will be
tripped by F160 fault).
Safety stop function takes priority over all other functions of the inverter.
This function should not be used as a control for starting and/or stopping the inverter.
3.2 STATE OF INVERTER, FAULT AND ALARM RELATED TO SAFETY STOP FUNCTION
Table 4: State of inverter, fault and alarm related to safety stop function
State / fault / alarm
Description
Cause
STO state
Safety stop
activated
Voltage between terminals 1 and 3 (relay K1 coil) and between
terminals 2 and 4 (relay K2 coil) of XC25 higher than 17 V.
F160 fault
Safety stop
function fault
It’s applied voltage to relay K1 coil (STO1) but it’s not applied
voltage to relay K2 coil (STO2) or vice-versa or there is a delay
of more than 100ms between one signal and the other. To solve
it, correct the external circuit that generates STO1 and STO2
signals.
A170 alarm (only on
CFW70x inverters with
software version V1.02
or higher)
Safety stop
activated
Only for keypad indication purpose, this alarm is indicated in
CFW70x inverters when the state of inverter is switched to STO.