From RSI - Robotic Systems Integration - SynqNet Systems
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eZMP System Power & Environment Requirements
Power Distribution Diagram
The eZMP requires an external DC power source. The power distribution drawing that follows shows an eZMP connected to a SynqNet Drive. The DC power source is connected to the eZMP system through a 3-pin connector. It plugs into the power connector of the eZMP. The ground from the power source and ground from the eZMP must be connected to the Single-Point Ground (SPG).
Devices connected to the hardware may have their own power sources for input data or output control signals. You can use other wiring setups, provided that each one is:
- at the correct voltage and current levels for the module and the device.
- connected to the same Single-Point Ground used by the eZMP.
It is recommended that the same main disconnect switch be used for the eZMP system and for all devices in the application.
Grounding the System
The ground of the eZMP power source must be connected directly to a Single Point Ground (SPG) tie block. The tie block should be made of brass or copper, bolted or brazed to the control cabinet. If the tie block is bolted rather than brazed, scrape away paint or grease at the point of contact. Put star washers between the tie block and the cabinet to ensure good electrical contact.
Metal enclosures of power supplies, drives, etc., should also have good electrical contact with the SPG.
Devices to be connected directly to the Single Point Ground include:
- Plant safety ground
- Chassis ground from eZMP power connector
- The metal panel or cabinet on which the eZMP is mounted.
- “Common” or “0 V” lines from power supplies that provide external power to the I/O modules and the devices to which they are connected.
- Chassis grounds from the devices themselves, such as device drivers, machinery, and operator interface devices.
- AC common line from the noise filter, if any.
- The ground of the power source of the computer workstation, if any, from which you monitor the system operation. An AC outlet in the control cabinet is recommended.
- Single point grounds from other control cabinets, if any, in the system.
Also, you must ensure that the eZMP "Chassis" connection is connected to SPG, and that the eZMP is mounted to a metal panel or enclosure that is connected to SPG.
Controlling Heat within the System
The eZMP hardware case is designed with ventilation hole to promote air circulation and dissipate heat. When mounting the eZMP, do not cover or obstruct the ventilation holes and observe minimum clearance requirements specified in the Mounting Instructions section.
Normally, no fans or air conditioners are needed. However, if the environment outside the control cabinet is hot or humid, you may need to use a fan, heat exchanger, dehumidifier or air conditioner to provide the correct operating environment.
Make sure that components installed in the cabinet with the eZMP do not raise the temperature above system limits and that any hot spots do not exceed specifications. For example, when heat-generating components such as transformers, drives or motor controls are installed, separate them from the system by doing one of the following:
- Place them near the top of the control cabinet so their heat output rises away from the eZMP.
- Put them in another control cabinet above or to one side of the cabinet with the eZMP. This protects the eZMP from both heat and electrical noise.
The eZMP itself is a source of heat, though in most installations its heat dissipates without harmful effects. System heat is generated from power dissipated by:
- field side input/output components
- other components within the eZMP
Handling the eZMP-SynqNet
The case protects the eZMP’s internal circuitry against mechanical damage in shipping and handling. However, like any electronics device, the circuitry can be destroyed by:
- temperatures over 55° C (131° F)
- moisture condensing inside the module
- static discharge
- exposure to a magnetic field strong enough to induce a current in the circuitry
- freezing temperatures, vibration, and other hazards
Recommended Signal Separation
Low level signals (encoder, analog, communications, fast DC inputs) should be separated from high voltage (110 Vac, 220 Vac, 440 Vac, etc.) or high current lines (such as motor armature cables). Maintain at least one inch of separation around signals.
Do not operate transmitters, arc welding equipment, or other high noise radiators within one meter of an enclosure that has the door open. Be sure to equip inductive devices, if they are in series with a mechanical contact or switch, with arc suppression circuits. These devices include contactors, solenoids and motors. Shield all cables that carry heavy current near the system, using continuous foil wrap or conduit grounded at both ends. Such cables include power leads for high-frequency welders and for pulse-width-modulated motor drives.
Information taken from Danaher Motion.