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NOVATEK-ELECTRO
UBZ-304
After UBZ energizing before the output relay will be on, it is necessary to check the insulation level of stator winding
relative to the housing. The level of stator winding insulation relative to housing is also checked, when the load relay is
on, but the motor currents are less than 10% of rated current (in this case UBZ considers that the motor is off).
When
“Insulation Mr” = “5 AR” (“5 nAR”)
the load is disabled if the insulation resistance is lower than 500 kOhm
±
20
kOhm, and when
“Insulation Mr” = “10 AR” (“10 nAR”)
if it is less than 1000 kOhm
±
50 kOhm. During automatic restarting
“AR”,
the
load will on after restoring the insulation resistance and after ARS time finishing. If “nAR”, ARS will not on
.
3.4.14 Protection for the motor phase (-s) break (loss)
is enabled, if one of the motor phase current is more
than 10% of the rated one (
“Rated Inom”
parameter), and any of the remaining phases of the motor is less than 7%
of the motor rated current.
3.4.15 Serviceability check of external magnetic starter
UBZ detects the motor currents when the load relay is off (if the load relay and functional relay is off in star-delta
mode). In this case, UBZ indicates the fault of external MS enabling the motor, until then UBZ is turned off or control
of the motor currents is disabled when load relay is off (Cont Cont
= 0 ("Off") parameter).
4 UBZ DESIGN
UBZ is microprocessor-based digital device that provides a high degree of reliability and accuracy. Operational
power is not required. The controlled voltage is simultaneously the power supply voltage.
5 INTENDED USE
5.1 PREPARATION FOR OPERATION
5.1.1 Preparation for connection:
–
Unpack the product (we recommend to keep the original packing for the entire warranty period of the product
operation);
–
Check the product for damage after transportation; in case of such damages detection, contact the supplier or
manufacturer;
–
Check for components (it.2), in case of detection of incomplete product, contact the supplier or manufacturer;
–
Carefully study the Operating Manual (
pay special attention to the connection diagram to power the
product
);
–
If you have any questions regarding the installation of the product, please contact the manufacturer by
telephone number indicated at the end of this Operating Manual.
5.1.2 Selection of Current Transformers (CT)
–
Rated output current of CT should be 5A.
–
Rated input current of CT (Ict) is selected based on the rated current of the motor (In), the motor starting
current, start duration, the time required for ARS (taking into account the characteristics of UBZ inputs designed to
connect CT (Table 5.1)).
Table 5.1
–
Characteristics of UBZ-304 inputs designed to connect CT
–
Current of UBZ inputs
designed for measurement
of CT output currents, A
Ratio of overload relative
to rated current (5A)
Maximum duration of
current action, s
Minimum delay before
restarting, s
0
–
12
2,4
continuously
-
12
–
15
3
60
10
16
–
20
4
30
15
21
–
25
5
15
30
ATTENTION: MAXIMUM CURRENT OF UBZ INPUTS DESIGNED FOR MEASUREMENT OF CT OUTPUT
CURRENTS IS 25 A.
Rated input current of CT should be within the range: In<Ict<3*In.
It is recommended to use CT with Ict=2*In.
5.1.3 General
ATTENTION! ALL CONNECTIONS MUST BE PERFORMED WHEN THE PRODUCT IS DE-ENERGIZED.
To ensure the reliability of electrical connections you should use flexible (stranded) wires with insulation for
voltage of not less than 450V, the ends of which it is necessary to be striped of insulation for 5±0.5 mm and
tightened with bootlaces. Recommended cable cross section for connection is not less than 1 mm
2
.
Wires fastening should exclude mechanical damage, twisting and insulation abrasion of wires.
IT IS NOT ALLOWED TO LEAVE EXPOSED PORTIONS OF WIRE PROTRUDING BEYOND THE
REMOVABLE TERMINAL BLOCK.
For reliable contact it is necessary to perform tightening of screws of removable terminal block with the force
specified in Table 2.
To improve performance properties of UBZ, it is recommended to install fuses (fusible elements or their
analogues) in the following circuits (listed in the order required; a hyphen is the recommended fuse value):
1) UBZ power supply circuits (34, 35, 36
–
L1, L2, L3)
–
1 A;
