Monitored Data; Operation Principle - ABB REC650 Technical Manual

1MRK 511 287-UEN A
6.6.6
6.6.7
Technical manual

Monitored data

Table 63: LCPTTR Monitored data
Name Type
TTRIP INTEGER
TENRECL INTEGER
TEMP REAL
TEMPAMB REAL
Table 64: LFPTTR Monitored data
Name Type
TTRIP INTEGER
TENRECL INTEGER
TEMP REAL
TEMPAMB REAL

Operation principle

The sampled analog phase currents are pre-processed and for each phase current the
RMS value is derived. These phase current values are fed to the thermal overload
protection, one time constant LCPTTR/LFPTTR function. The temperature is
displayed either in Celsius or Fahrenheit, depending on whether LCPTTR/LFPTTR
function is selected.
From the largest of the three-phase currents a final temperature is calculated according
to the expression:
2
æ ö
I
Q = ×
ç ÷ T
ç ÷
final ref
I
è ø
ref
EQUATION1167 V1 EN
where:
I is the largest phase current,
I is a given reference current and
ref
T is steady state temperature rise corresponding to I
ref
Values (Range) Unit
- -
- -
- deg
- deg
Values (Range) Unit
- -
- -
- Temperature
Fahrenheit
- Temperature
Fahrenheit
ref
Section 6
Current protection
Description
Estimated time to trip (in
min)
Estimated time to reset of
lockout (in min)
Calculated temperature
of the device
Ambient temperature
used in the calculations
Description
Estimated time to trip (in
min)
Estimated time to reset of
lockout (in min)
Calculated temperature
of the device
Ambient temperature
used in the calculations
(Equation 16)
125