LS ELECTRIC SV-iS7 Series, User Manual

Page: 357 / 491

Using Protection Features
340
10.2.6 Dynamic Braking (DB) Resistor Configuration
The iS7 series is divided into a model which features a built-in braking circuit and the other in
which a separate external braking unit should be installed. 0.75
– 22 kW model types belong to
the former (braking resistor unit is excluded) and for those model types above 30 kW, you
should install a braking unit on the exterior of the inverter. Therefore the function of limiting
the braking resistance use rate (%ED) is necessary for only models below 22 kW.
Group Code LCD Display Parameter Setting Setting Range Unit
PRT 66 DB Warn %ED - 10 0 – 30% -
OUT 31 – 33 Relay1,2, Q1 31 DB Warn%ED - -
Dynamic Breaking Resistor Setting Details
Code Description
PRT-66 DB
Warn %ED
Sets braking resistor configuration (%ED: Duty cycle). Braking resistor
configuration sets the rate at which the braking resistor operates for one
operation cycle. The maximum time for continuous braking is 15 sec and the
braking resistor signal is not output from the inverter after the 15 sec period
has expired. An example of braking resistor set up is as follows:
%𝐸𝐷 =
𝑇_𝑑𝑒𝑐
𝑇_𝑎𝑐𝑐 + 𝑇_𝑠𝑡𝑒𝑎𝑑𝑦 + 𝑇_𝑑𝑒𝑐 + 𝑇_𝑠𝑡𝑜𝑝
× 100%
[Example 1]
%𝐸𝐷 =
𝑇_𝑑𝑒𝑐
𝑇_𝑑𝑒𝑐 + 𝑇_𝑠𝑡𝑒𝑎𝑑𝑦1 + 𝑇_𝑎𝑐𝑐 + 𝑇_𝑠𝑡𝑒𝑎𝑑𝑦2
× 100%