User Manual

(Revised 8/5/2009)

N-TRON SWITCH GROUNDING TECHNIQUES FOR 1000 SERIES

The grounding philosophy of an y control system is an integral part of the design. N-Tron swit ches are des i gned

to be grounded, but the user has been given the flexibility to float the switch when required. The best noise

immunity and emissions (i.e. CE) are obtained when t he N-Tron switch chassis is connected to earth ground via

a drain wire. Some N-Tron switches have metal din-rail brackets that can ground the switch if the din-rail is

grounded. In some cases, N-Tron switches with metal brackets can be supplied with optional pl astic bracket s if

isolation is required.

Users ma y run a drain w ire & lu g from t he scr ew provi ded on the back face o f the

enclosure. In the event the provided grounding screw has been lost, care should

be taken to limit the penetration of the outer skin by less than 1/4". Failure to do

so may cause irreversible damage to the internal components of the switch.

Note: Ensur e the power supply is grounded properly before applying power to the

grounded switch. This may be verified by using a voltmeter to determine that there

is no voltage difference between the power supply’s negative output terminal and

the chassis grounding point of the switch.

As an alternative grounding method, both V- legs of the power input

connector are connected to chassis internally on the PCB. Connecting

a drain wire to earth ground from one of the V- terminal plugs as

shown here will ground the switch and the chassis. The power leads

from the power source should be limited to 3 meters or less in length.

Note: Before applying power to the grounded switch, you must use a volt meter to verify there is no voltage

difference between the power supply’s negative output terminal and the switch chassis grounding point.

If the use of shielded cables is required, it is generally recommended to only connect the shield at one end to

prevent ground loops and interfere with low level signals (i.e. thermocouples, RTD, etc.). Cat5e cables

manufactured to EIA-568A or 568B specifications are required for use with N-Tron Switches.

In the event all Cat5e patch cable distances are small (i.e. All Ethernet devices are located the same local

cabinet and/or referenced to the same earth ground), it is permissible to use fully shielded cables terminated to

chassis ground at both ends in systems void of low level analog signals.

DRAIN WIRE WITH LUG CONNECTING SWITCH

CHASSIS TO KNOWN GOOD GROUNDING POINT .

DRAIN WIRE WITH

LUG CONNECTING

SWITCH CHASSIS

TO KNOWN GOOD

GROUNDING

POINT.

METALLIC

DIN-RAI L C LI P