Walker Magnetics IMI Smart-D Series, Operation Manual

800-WMAGNET

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4.8 Grounding & Shielding

The optional chuck control outputs for current sense and part released are isolated from the control circuit ground. All other 

chuck control electrical inputs and outputs, if connected to electronic equipment, must be isolated from the control’s internal 

circuit ground, which is connected to the AC safety ground (the green or green/yellow wire in the AC line cord). The base of 

the chuck is to be grounded to this point, as well as, through the ground wire of the DC chuck cable. All electrical chassis 

must be safety grounded.
The chuck control’s DC power output leads 

MUST BE SEPARATELY ROUTED

 from other 115V level power leads in the 

machine. They must not be routed in the same wire bundle with 400V or other high voltage leads. If the control has LOW 

VOLTAGE signal leads wire through the machine, these 

MUST BE SEPARATELY ROUTED

 in their own SHIELDED 

WIREWAY and the shield grounded to the machine chassis. Low voltage signals must not be routed with high voltage or high 
power cables through any part of the machine, or electromagnetic interference may result.

4.8.1 Current Sensing

This control is equipped with a current sensing feature that monitors the current flowing to the chuck and indicates when this 

current has reached a predetermined value. The predetermined value is set by adjusting the variable potentiometer to the 

desired point and then pressing the residual pushbutton while holding down the variable pushbutton. When the preset value 

is reached, the Variable indicator light stays on and the current sense relay closes. If the current flowing to the chuck goes 

below the preset value, the variable light will flash. See section 3.1.8 for more information.

4.8.2 Part Release

When the control enters the Full and Variable modes Part Release relay energizes. When the control comes to the end of a 

release cycle the Part Release relay de-energizes. See section 3.1.9 for more information.

4.8.3 Lockout

A Lockout feature is supplied with this control which prevents anyone from accidentally changing the settings while machining 

is in progress. When the lockout signal is low (0V), the feature is disabled and when the signal is high (+5V), the feature is 
enabled. The feature can be operated in two different manners. See section 3.1.10 for more information.

4.9 Control Output Voltage

The DC voltage for the magnet is connected across terminals 1 and 2 on TB1. This voltage may be measured 

across these terminals and can vary from 0 115VDC and 0-230VDC depending on the model control and its 

settings.