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9307391

    

 Ind Mod. 33119

Thermal Overload Relay
Current transformer operated

Fig. 2

Fig. 1

RTD180

Operating instructions

WARNING:

 

Hazard  of electrical shock. Installation and

maintenance by qualified personnel only.
Isolate before servicing. Follow the operating instructions.
Protection  degree IP00 with links, IP10 with MR3 terminal box and IP20
without links.

Specifications are subject to change without notice

         

          Main                        Connection size

            

      

 60-90A

               

Up to 50mm

2

   (1AWG)

               

80-120A

Up to 120mm

2

 (AWG4/0) with links for

connection as  indipendent unit or to GH15NT
and GH15PT  contactors
 With terminal box MR3-AD (optional) for
 connection with cable of 16-120mm

2

 (AWG5 -4/0) section

           

 Auxiliary    

                    

 Connection size

 

Flexible or stranded cable 2 x 0,75-

2,5mm

2

(AWG 18-14)

Flexible with multicore cable end
2 x 0,5-1,5mm

(AWG20-16)

1.

Configuration

The current transformer overload relay unit is supplied as independetly
mounted assembly.  It is provided with four fixings for panel mounting,
see fig.3.
The thermal overload relay  is a factory connected unit, being permanently
sited on top of the 3 phase current transformer assembly mouldings.
Mounting position: any vertical plane orientation within  ±30°.
The relay is suitable only for a.c. current 50-60Hz.
Trip class to IEC 60947-4-1: class 10A.
2. Cabling

           120-180A

2.1.Main connection
Torque:M8 screws = 17Nm (150 lb.in)
For current up to 120A the current transformer unit permits the use of
conductors through the central core hole for each phase connection.
For higher current suitable connecting links are available.
For single phase loads the three main circuits must be series connected.

2.2.Control connection
Torque: M3.5 screws =1-1.3Nm (7 lb.in)
Using correctly size cable, connect the operating coil of the associated
contactor in series with the NC contact of the relay i.e. 95-96.
If a signalling device has to be energized when the relay trips, connect it in
series with the NO contact, i.e. 97-98.
The NC circuit is electrically separate from the NO circuit  up to 440V
(150 V AC for UL standard).
3.

Setting to full load current of the motor

The relay is set to the full load current of the motor (primary current) by
rotating the adjustment dial .1 (fig.2) until the arrow head correspond to the
value of current.
The secondary current for the adjustment of the relay is one hundredth of
primary current.
Example:

rated load current 120A
setting of relay

1.2A

Three phase wiring  diagrams

Single phase wiring  diagrams

Contactor

O/L

Contactor

O/L

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