Novatek THREE-PHASE POWER LIMITER OM-310 OM-310 Data Sheet

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NOVATEK-ELECTRO

 

t1F - time, during which the load relay will be open after de-energizing resulting from the watts input crossing 

the main threshold 

 

Figure 1.2 - OM-310 operation in the power limiting mode when 

=0, =1, =3 

 

 

1.2.5.3 Active power limiting during operation of a characterizing relay at 

= 2 ( relay used for connecting ad-

ditional load) 

After 

ОМ-310 energizing, after AR time (Att parameter) the load relay will close.  After the delay, defined by 

“

” or “” parameter (whichever time is longer), the characterizing relay closes while connecting additional load. 

If during operation the active power consumed by the load crosses the additional threshold (line 2 figure 1.3) for a 
time period that is longer than assigned by “

” parameter, the characterizing relay will open.   

Characterizing relay will re-close again: 
а) at  =0, after time, assigned by t2F parameter (instance of the characterizing relay closure - line “b” on 

fig.1.3.); 

b) at  

=1, when  load consumed power will reduce till the additional load power-on threshold (line  3 on 

fig.1.3) (the characterizing relay engaging point - line “a” on fig.1.3.); 

c) at  

=2 depending on which event (a or b) comes first. 

If during operation the active power consumed by the load crosses the additional threshold (line 1 figure 1.3) for 

a time period that is longer than assigned by “

” parameter, the characterizing relay and the load relay will open.  

The load relay and characterizing relay will be re-closed after AR period, or after time specified by 

 parame-

ter (whichever of the time periods is longer) (Figure 1.3). 

 
 
 
 
Load consumed input wattage 
 
 
 
 
 
 
 
 
 

Characterizing relay in the mode of controlling 
additional load 

 
 
 
Load relay 
 
 
 
1 – main threshold  (“

” parameter) 

2 – additional de-energize threshold  (“

” parameter) 

3 – additional energize threshold  (“

” parameter) 

 

Figure 1.3 - OM-310 operation in the power limiting mode when 

=2 

 

The wattages values for the main threshold, the additional threshold, and the additional load energize threshold  

depend on the “

” parameter value.  

When 

=0, the load consumed power is calculated for each phase separately and is compared with the thre-

sholds calculated as: 

Main threshold (kW) = (“Pnn” * “P1F”) /(100*3), where 
 “Pnn” – cumulative rated load wattage, kW; 
 “P1F” – main threshold, %. 
Additional threshold (kW) = (“Pnn” *  “P2F”) /( “100”*3), where 
“P2F” – additional threshold, %. 
 
When 

=1 the main threshold, the additional threshold and the energizing threshold are calculated similarly to 

the way described under paragraph 1.2.5.2