Electrical Requirements to Know Up Front
Machine electrical requirement are a common source of confusion. In North America, voltages vary widely. You will be asked about your power requirements when ordering new equipment. Power available in your shop is THREE PHASE or SINGLE PHASE. Some facilities have both single and three phase power. Look and determine if your supply cords, breaker boxes or disconnects have 3 wires total (Single Phase) or 4 wires total (3 Phase).
If your power supply is Three Phase, you will have 3 hot legs + 1 ground for a total of 4 wires for connection to your new bending machine. If you have single phase, you will have 2 hot legs + 1 ground for a total of 3 wires. Your system ground wires are most probably green. Your new bender, if supplied with a courtesy “pig tail”, will have a green and yellow striped ground wire. Common single phase voltages in the USA are generally 208V, 220V or 230V. Common three phase voltages can range from 208 volts to 480 Volts. Machine voltages are not changeable between single and three phase. Some Three Phase machines can be rewired to line voltages from 208 to 480V and other cannot. Motors 5HP and larger are generally dedicated and cannot be rewired for another voltage.
When three phase machines are rewired from 220V to 440V or 440V to 220V you must make sure ALL of the electric motors are rewired, fuses are changed appropriately, overload relays are set to the proper amperage and the control transformer is connected to the proper voltage taps.
Both Carell Corporation and Eagle stock machines in various voltages, however you must be positive of your requirements at the time of order. Owners, purchasing agents and others not physically involved in the facility’s power grid are often unaware of voltage requirements and must rely on others to convey accurate information. Machines connected to a voltage other than that specified on the bender will almost certainly suffer permanent damage. Power requirements are fundamental, like knowing whether to put diesel or gasoline fuel in your automobile. Making the wrong choice will always be costly. Read your paperwork, order confirmation, power requirement labels located on the machine and in the unit’s electrical cabinet. Once you turn on the “juice”, it is often too late.
If you have questions with electrical or any other technical aspects of your Eagle or Carell machinery, call and speak with one of Technicians. T (251) 937-0947
Start Up of Your Single Phase Bending Roll – Roller Rotation
Small Section Benders, Universal Roll Benders or Angle Rolls which are electro-mechanical and require a single phase power supply require proper phasing to operate properly. Your machine will have foot pedals, push buttons or a selector switch to change the rolling direction from clockwise to counter clockwise or in other words forward to reverse.
If you press the left foot pedal or turn a selector switch to the left or press the left side push button, your material should move from right to left. On a 3 Roll Section Bender, when facing the machine, the lower rolls should turn counter clockwise and the top roll, if powered should turn clockwise. If the machine moves the material in the opposite direction of that corresponding to the controls, simply invert the position of the 2 individual “phase wires” at your power connection. These two wires are sometimes referred to as your “hot legs”. Do not confuse these with your ground wire!
Swapping the positions of the 2 phase wires will reverse the rotation of the electric motor. Your controls will now correspond with the proper shaft rotation and the material movement through your machine will match the appropriate controls.
If you have issues in powering up your mechanical Angle Roll, Section Bender, Plate Roll or other Carell or Eagle equipment, please call our Technical Department at: 251-937-0947 and ask for assistance.
Start Up of Your Hydraulic Bending Roll – Pump Activation
Proper initial start up of machines with hydraulic powered functions is critical and is a common source of technical calls to the supplier or manufacturer.
Most Carell Corporation and Eagle Bending Machines, Inc. Roll Bending Machines, Angle Rolls, Section Benders, Plate Bending Rolls and Horizontal Presses have some hydraulic powered functions. Hydraulic system pressure is generated by a hydraulic pump. Hydraulic pumps are powered by electric motors. Hydraulic pumps will only generate system pressure when they are turning in the correct direction. Since electric motors will run in both clockwise and counter clockwise rotation directions, proper phasing at your main electrical connection is essential.
The majority of Bending Machines employing hydraulic powered movements require a three phase power supply. Three phase power entrances all include 4 wires (3 individual hot wires + 1 ground wire). Whether you have a 3 phase 208, 220, 230, 440, 460, 480, 575 or 600V power supply in your facility, the phasing of your 3 “hot legs” or “phase wires” will determine whether the motor driving the pump turns CW or CCW.
If your machine “turns ON” with the control panel and/or other lamps and indicators illuminated and your hydraulic movements do not react or respond to the pushbutton controls then chances are that you are “Out of Phase”. In other words, the electric motor is ON and you hear the hydraulic unit running but the motor is turning backwards and thus the pump is not generating pressure. The pump is then running “dry”, no oil is passing through it but it is turning. This can cause serious and permanent damage to the pump. TURN OFF YOUR MACHINE IMMEDIATELY! You are running the pump dry and its inner walls may score or burn.
To correct this situation, simply swap positions of two of the three “Hot” leads at your connection point which may be at the plug on the pig-tail power cord of the machine or the hardwire junction box nearest the machine. This will reverse the electric motor rotation; the pump will turn in the appropriate direction so that the hydraulic pump will generate pressure.
If you have issues in powering up your hydraulic Angle Roll, Section Bender, Plate Roll or other Carell or Eagle equipment, please call our Technical Department at: 251-937-0947 and ask for assistance.
Start Up – The Importance of Proper GROUNDING
Section Benders, Universal Roll Benders, Angle Rolls, Tube/Pipe Benders, Plate Rolls, Rebar Benders and all other Metal Fabricating Machines are equipped with an integral ground circuit. The machine ground MUST be properly connected to your shop’s ground circuit. If a Carell or Eagle machine is equipped with a pre-installed courtesy pig-tail, the ground wire will be green and yellow stripped. If the machine does not have a courtesy pig-tail, the ground terminal in the electrical cabinet will be adjacent to the main feed terminals. The ground terminal module will be yellow, green, yellow/green or have a ground symbol that is evident.
The electrical system in your facility MUST have a ground circuit. The ground wire at your power connection point MUST be connected to the machine at the ground terminal inside the machines’ electrical cabinet. Mistakenly connection your ground wire to one of the “hot leads” or phase wires on the machine will damage your equipment. Connecting one of your “hot leads” to the machines ground wire terminal, which is the same as above, will damage your equipment and is extremely dangerous. To make a point, even your home has ground fault circuits and your lawn extension cords have a ground terminal. You know that attention to the condition of the ground wire is of utmost importance and improves the safe operation of all electric powered equipment.
To determine if you have an issue in your grounding circuit you should always use a hand held volt meter. With the machine OFF, check the voltage between the ground wire and each of the phase wires. If you show voltage on your ground wire, you have “back feed” and the issue with your system MUST be corrected immediately. It is prudent to provide a ground to earth rod near any machine having more than 10HP. An “earth ground” should be installed as close to the machine as possible. Safety is one of our primary concerns. However, it is the machine owner/operator who must ensure that the shops’ electrical system is adequately maintained, is in proper working order and that electrical terminations to new equipment are properly made. Consult local, state and federal regulations as a licensed electrician may be required to make final connections from your power grid to your new machine.
If you have issues regarding start up of your Roll, Section Bender, Plate Roll or other Carell or Eagle equipment, please call our Technical Department at: 251-937-0947 and ask for assistance.