Suni Cranes Controls

Vasai, Mumbai, Maharashtra

Controlling motors with resistors is a universal method of speed control. The resistors are used to limit the in-rush current and adjust the torque and speed characteristics of an ac and dc motor

By changing the resistant on the rotor (through contactor), you can limit the starting torque and speed of the motor for your specific application.

Suni make Resistance Box /Resistors are designed to meet requirements of A.C & D.C. application for E.O.T. Cranes, Winches, Rubber Mills, Flour Mills, Coal Mines, Cement Mills, Power Plants, Conveyors, Coke Oven, Blowers etc. for Speed control and developing Starting Torque.

ENCLOSURE FEATURES

• overhung top with canopy to prevent standing water and will support heavy ice and snow.
• Forged eyebolts are provided in all four corners for easy handling.
• Removable front and rear louvered covers for easy access for connection and inspection.
• Corrosion resistant nameplate provides complete ratings and manufacturer's information.
• Galvanized Iron Sheet provides maximum protection.

ENCLOSURE OPTIONS

• Aluminum, mill galvanized, stainless steel and hot-dipped galvanized construction.
• Custom paint finish is also available.
• Top or side mounted entrance bushing(s).
• Screened covers for indoor applications.
• Support stands for elevating the enclosure above ground.

Stainless Steel Punched Grid type Resistors

These are designed and manufactured for current ratings form 10 Amps. to 234 Amps. Continuous Resistors of higher ratings are manufactured by using 2 or more parallel paths. Resistors with short time ratings up to 3000 Amps. or even more for neutral grounding are possible which are suitable for system voltage up to 11 KV and above

Resistors can be designed to BSS / VDE/NEMA/IEEE or any other requirement specified by customer. The Temperature rise for stainless steel wire and Punched steel grids is 375*C. Resistors can also be supplied for lower temperature rise such as 220*C etc. by suitably de-rating the grids. Resistors for higher temperature rise can also be designed for short time duty e.g. 760* C for stainless steel which is permitted by IEEE Standard 32

Suni makes Flameproof (FLP/WP )Rotary Gear type Limit Switch that is used on Control / Power circuit of reversing drives so as to limit their rotation / movement within a predetermined position.The Flameproof (FLP/WP) Rotary Limit switch FlameproofTesting as per IS/IEC 60079-1:2007 & Dust ignition protection as per Is/IEC 60079-31:2008 & Weatherproof Testing as per IS/IEC 60529:2001 for IP 66 Enclosue Material is in Die Cast Aluminium Ally LM6 & used in Zone 21, 22 & 1&2, for gas Group-IIA, IIB & IIC atmosphere

The function of the Limit Switch is to stop the mechanism of drive at the extreme clock wise / anti clock wise position. Suni Make Rotary Limit Switches are particularly suited for use on reversing drives such as Electric Hoists, Winches, Over Head Cranes, Traversers etc. The contacts of these Limit Switches are rated for 40 amps at 500 Volts A.C.The Limit Switch can be provided with 2NC contacts or (2No + 2NC) contacts as per the requirement.The geared type rotary limit switch basically consists of heavy duty worm gear drive with a ratio of 48:1 The Crane Duty Rotary Geared Limit Switch is made in IP-66 enclosure.

in case of IP-66, the cover is of cast Aluminum. Also the Base and cover have machined surface to protect the Limit Switch against dust.The cam shaft which extends from behind the gear into the Aluminium housing accommodates the cams.

2 or 4 cams are used depending upon whether the Rotary Limit Switch is of 2 contacts or 4 contacts operation.The contacts have a maximum continuous Current capacity of 40 amps AC.The contact tips are made of high grade Silver Cadmium Oxide alloy.

When used for Series operation [up to 40 Amps maximum], the Contacts are suitable for 720 operations per hour and in case of Shunt operation [ for Control Circuit ] , the Contacts are suitable for 1000 operation per hour.The same Contacts can be used in Series as well as in Shunt configurationsThe switching capacity of the Contacts when used for Shunt operation is 15 amps at 400 Volts, AC on highly inductive load and 2.5 amps at 220 Volts DC.These switching capacities in fact are far in excess of what is actually required in practice and hence replacement of Contacts for Shunt may not be necessary for a long time.The body of the Contacts is made of high grade Melamine which is specifically suited for heavy duty operation .The material is non – tracking and is capable of with standing heavy arcing.The FLP/WP Rotary Limit Switch operates in the following manner:The Mechanism or the Drive coupled to the Limit Switch actuates the Contacts through the Worm Gear Drive and the Cams.When the Mechanism or the Drive approaches the pre determined position, the Cam strikes the Contact finger of the corresponding Contact which in normal condition is in a closed position. This immediately opens the Contacts and the Circuit is broken there by disconnecting the respective Motor from the supply and resulting in the stoppage of the Drive or Mechanism.The Actuator or Cam is provided with a maximum follow-through angle of 60 degrees there by ensuring that the normally closed Contact, which has been opened by the Actuator / Cam, shall remain in the open position for at least 8 full additional revolutions of the Input Shaft.This provision is adequate for most of the Reversing Drives where the Mechanism or Drive comes to a complete stop with in 1/5th of a revolution of the Input Shaft of the limit Switch.In addition to the adjustment provided for the Actuator/Cam a further fine adjustment knurled Screw is provided for each Contact. This adjustment can be locked in position by locking Screws provided with each Contact fitting.

Suni Brand Grab differential Limit Switch is driven by holding and closing winches is used in auxiliary circuits for single lever grab control.

It is used for stopping the closing motor after closing or opening, regardless of the height of the grab and starting the holding motor after closing, for transition to the hoisting action as well as for stopping the holding & closing motors at the hoisting & lowest grab position.

Construction :

The switch contains six cam operated switch elements which are used as auxiliary circuit limit switches (See switching sequence diagram). The dimension drawing shows that the switch has two shafts which must be driven by the holding and closing winches. The contracts of limit switches are 40 Amps rated at 500 V. A. C.

Mode of operation :

The switches N5, N6 are limit switches for the highest and lowest grab positions. The 'Grab closed' and 'Grab open' limit positions are monitored by the switches N1 & N4, whereas N2 & N3 initiate the switching operations for single lever grab control.

Installation :

The switch is best arranged to one side of the winch space between the drums where it should be easily accessible. It can be mounted either in a horizontal or a vertical position. However, the former is preferred since the switching equipment and gearing can be reached more easily when the cover has been removed. Auxiliary shafts connected to the winch of the grab hoisting gear are best used for driving the switch. The closing winch is connected to shaft 1 at the differential gear end and the holding which is joined to shaft 2 at the same or opposite end of the switch.

Accessories :

A special wrench is needed to release the locking nut when adjusting the cam discs. This wrench is included with the switch.

Description:

• We are well reckoned as the most preeminent Master Controller Manufacturer and one of the leading Suppliers of the same. Suni Master / Cam controllers are made in IP 54 enclosures. the cover is of cast Aluminum. Also the base and cover of Crane Master Controller have machined surface to protect the controller against dust.
• The Master / Cam Controllers are provided with an easily removable cover having ample area for easy maintenance.
• The cam shaft on which the cams are fitted is mounted in the housing on moulded bushes of synthetic material which are fixed to the front and rear walls by means of screws.
• The cams which are fitted on the cam shaft are moulded from the highest quality synthetic material and are accurately cut to correspond to the switching sequence and number of steps required by the customer.
• The controller is operated by means of a joystick handle which rotates the shaft on which the cams are fixed. These cams which are cut as per the sequence required open and close the fixed and moving contacts which in turn operate the required Contactors in the panel provided by the customer.
• Contact body of Mill Duty Master Controller is made of high grade melamine which is capable of one auxiliary contact of two contact block (1 No. + 1 NC) operated through a spring loaded push button provided on joy stick handle.
• The Master / Cam Controllers can be provided with spring return arrangement whereby handle returns to be neutral position when it is released.
• The contacts have a maximum continuous Current capacity of 40 amps AC.
• The contact tips are made of high grade Silver Cadmium Oxide alloy.

As a trustworthy organization of this domain, we are committed to offering our clients a superior quality assortment of Brake Drum Coupling.

We are highly respected as established manufacturer and exporter of Gear Coupling. These are precision engineered by using high-end technologies in sophisticated facilities.

Suni Make Flameproof cum weatherproof (FLP/WP ) junction box in cast aluminium LM6 with multiple ports and cable glands for intlet and outlet connection of loadcells in compliance with requirements in respect of flameproofness and temperature class suitable for use in Zone 1 & Zone 2 and gas groups IIA & IIB atmospheres. Certified by Central Institute of Mining & Fuel Research (formerly known as Central Mining Research Institute, CMRI, Dhandbad).

Suni Make FLP/WP Junction Box is Flamproof Testing as per IS/IEC 60079-1:2007 & Dust Ignition protection as per IS/IEC 60079-31:2008 & Weatherproof Testing as per IS/IEC 60529:2001 for IP 66 Enclosue in die cast Aluminium alloy LM6 for used in Zone 21, 2e2 and 1 & 2 for Gas Group: IIA , IIB & IIC atmospheres.