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1s . 30s, with steps 0. new start-up possible
after the current has dropped below this threshold.2. The other characteristics are the same those for thermal memory
"L" (see par.
Model 2234 Apparatus Scale
L2778
Doc.2.1In steps).9 escription the protection functions
14.1). This parameter automatically calculated setting
the parameter (required trip time 3xI1).1 Protection "L"
The "L" the only protection that cannot disabled because for self-protection against overloading the relay itself..Watchdog for proper connection the trip coil (TC).2 Start-up threshold "S"
The start-up function can selected the case where the curve with fixed time selected.
The start-up function enables the protection threshold (S, and changed during time interval lasting "ts", starting from "start-up".
Standard trip curve according IEC 60255-3
There are types curves settable, defined the IEC standard 60255-3 and C.9.25xI1.B.: The thermal memory function can only set the type curve selected the standard one (t=k/I2) (see par.01s.2.9.
14.2.2 Protection "
This protection can disabled; can the fixed time (t=k) inverse time (t= k/i2) type.9. enabled, any anomalies are indicated special alarm message and the "alarm"
LED coming on.
The protection trip time inverse time given the expression:
9 ,
, where 12ln, where 12ln where the fault current andI1the protection threshold..g.
The protection trip time inverse time given the expression:
k f
t where the fault current and I1the protection threshold specified the user. the PR120/D-M module installed, this activates the coil opening command (YO), thus opening the CB..9.9. This based the
"tS" parameter defined the trip time the curve (t2) selected 1.2.1 Thermal ory "S"
The thermal memory function can enabled for cable protection the case where the curve with inverse time selected.
N.
14.
Ith
1
Start Threshold I2
Threshold I2
Start Up
Programmed time ts
• Start-up tim e
The start-up time common all the protections involved.2.1.
□ Watchdog for protection Trip.
The function can disabled and setting characteristic the single protection units.
14.
14.2. 14.
Otherwise, the trip time will reduced, depending the overload which has occurred and the time that has elapsed.2. 14.2. the latter case, the trip time given the expression:
100 t,
- t
\2 where where the fault current and I2the protection threshold. enabled, the event the sensors being disconnected Rating Plug error, opening command
is given the being enabled.
a and are two parameters, suggested the standard, which vary the type slope selected (e.10In, 0.1.
79/158
. for type slope a=1 and k=13.5xI2.
V )
NB: Time expressed seconds.
Range: 0.5);
b parameter introduced SACE increase the number curves with the same slope.1 Thermal ory "L"
The thermal memory function can enabled for cable protection.9. The release trip time certainly 100% the one selected, after interval has passed since the last overload since the last trip.
4. The
latter must intended follows:
- Passage the RMS value the maximum current over one single adjustable threshold (0. based the''TL" parameter defined the trip time the curve (t1) selected
at 1.
It the PR123/P release that automatically decides which the two use, according the various situations.2. The first only effective when the release powered (it also records
overloads that have not lasted long enough trip the release), while the second works even when the release not powered, reducing any trip
times the case immediate reclosing and enabled soon the tripped.
The PR123/P fitted with two instruments make this thermal memory. 2
Page No. The types trip curves
settable are divided into two groups according the standard they refer to.1).
Standard trip curve according IEC 60947-2
Only one type curve settable (t=k/I2) defined the IEC standard 60947-2. No.
NB: Time expressed seconds.1.9.
