Neutral adjustment. Crate LS1-131

adjustment

The neutral protection is normally set to a current value 50% of the adjustment made on the phases.

In some installations, where particularly high harmonics occur, the current circulating on the neutral may be higher than that of the phases.

I

In the SACE PR122/P release, this protection can be set for the following values: n

N= 50% - 100% - 150% - 200% * I n

.

13.5.4.2.1 Neutral adjustment specifications

Neutral (InN) adjustment must meet the following formula: I

1 x I n

NIu.

In case of a four-pole CB, this setting is checked by the relay which signals any failure through a Led (see par. 13.6.1), and adjusts the parameter independently to the accepted limits.

In case of a three-pole CB with external neutral, the relay performs no checks and user must correct the settings.

E.g.: With CB E1B800 with a 400A Rating Plug, Iu = 800A and I1 = 1In, I n

With CB E1B800 with a 800A Rating Plug, Iu = 800A and I1 = 1In I n

N adjustment may be: 50-100-200%.

N adjustment may be: 50-100%.

Note 1: I

1

=1I n

setting is intended as the maximum adjustment of the protection against overloads. Actual maximum allowable adjustment must take into account any temperature derating, terminals used and altitude, or In (rating plug)≤ 50% of circuit breaker size.

WARNING: Failure to comply with the setting limits for “I

1 consequent risks even for the operator.

” and “I n

N” can cause circuit-breaker damage with

In any case, the relay records any setting error between I

1 par. 13.6.3). For four-pole CBs only.

and the Neutral setting and it signals this by means of the warning (see

13.5.4.3. Mains frequency settings

In the mains frequency menu, you can choose between the frequency values: 50, 60Hz.

2/8 Password

1/2 Settings

Circuit Breaker

Main Frequency

Modules

Enter 

0***

Mains Frequency

50 Hz

60 Hz

4 P

50 Hz Enter password

Enter 

13.5.4.4. Modules

When you access the Settings menu, there is a set of menus available relating to the modules.

13.5.4.4.1 PR120/V MEASURING Module

1/4 1/5

Modules

MEASURING module

COM module

SIGNALLING module

MEASURING module

Voltage Transf

Rated voltage

Positive Power flow

Absent

In the measuring module you must enter a password and can then opt for the absence or presence of the voltage transformer.

Moreover, you can select the values of the primary voltage (100, 115, 120, ... 1000V) and secondary voltage (100, 110, ... 230V).

The power flow can be LOW  HIGH or HIGH  LOW. After entering a password you can choose whether the neutral connection is to be Absent or Present. For three-pole CBs only

13.5.4.4.2 PR120/D-M - COM module

Modules 2/4

MEASURING module

COM module

SIGNALLING module

Communication parameters

COM module

Local / Remote

Serial Address

Baudrate

1/5

Local

The local or remote modes can be selected after entering a password. The serial address can be displayed after entering a password. The Baud Rate can be set on the values 9600 and 19200 bit/s. The physical protocol provides for the options: (8,E,1),

(8,0,1), (8,N,2), (8,N,1). The addressing can be selected as standard Modbus or ABB. For further information on the PR120/D-M communication module, see paragraph 15.2 in this manual..

13.5.4.4.3 PR120/K - SIGNALLING module

For a thorough examination of the signalling module, refer to the corresponding section of the module, paragraph 15.3.

13.5.4.4.4 PR120/D - BT module

This module is for wireless communication based on the Bluetooth standard between the PR122/P protection release and a laptop with a Bluetooth port. For further information, see the description of the module in paragraph 15.4.

13.5.4.4.5 Settings for the Local Bus unit

If the PR021/K unit is connected, you need to enable the local bus by selecting present.

Model L2234

L2778

L4681

L5179

L5439 Apparatus

Doc. no.

Emax

1SDH000460R0002

Scale

Page No

76/161