Accumetrics AT-4500 EasyApp Quick Manual

AT-4500 EasyApp Quick Guide

1. Plug in the receiver and attach the power and data cables from the receiver to the tuning enclosure.

2. Attach the 8 gage Litz wire cable from the tuning enclosure to the stationary pickup coil/ loop. Don’t

change the length of this cable.

3. Hold the transmitter axially centered and an inch from the inside diameter of the loop. Observe if the

LED’s on the receiver front panel register good data signal strength, and that the red front panel LED

indicating “induction power low” is not illuminated.(Note: Refer to the manual for optimizing the RF

tuning; the system may have been tuned for use near metal. Tuning is needed for layout change).

4. Locate one of the included six inch long input cables, and temporarily solder or clip-lead each of the

cable wire ends to quantity 4 of 1000 ohm or higher identical resistors. Short the free ends of the 4

resistors together to make a “star bridge” (a substitute for using a known good full bridge strain gage).

5. Remove the four screws and the transmitter front panel cover and connect the input cable with the

“star bridge” to the 4 pin female socket.

6. Connect a DC voltmeter to pins 13 (voltage output) and 25 (signal ground) on the receiver rear D-

connector. As seen from the back of the receiver, pin 13 is the top left pin; pin 25 is the bottom left pin.

7. Hold the transmitter near the loop. With the shunt cal light off, then a roughly zero volt signal output

should be seen when the “star bridge” is connected to the input. If shunt cal is “on”, then press the front

panel button to reset, as this feature does not work with a “star bridge” unless the star bridge resistors

are selected carefully (see Vishay application note VMM-7).

Initial Shaft Test:

1. Mount the base of the pickup loop to a rigid surface, so that the loop is axially and radially aligned

with the transmitter. Attach the transmitter to the shaft by use of the appropriate Kevlar straps and the

yokes. (See Section 8 of the manual and any specific engineering recommendations for tightening).

2. Connect the system to a conventional full bridge strain gage (350 or 1000 ohm). This will allow you to

see torque/strain effects, and the effect of toggling the shunt calibration on/off from the receiver

control.

3. Rotate the shaft and monitor the torque output with a DC voltmeter (pins 13 (voltage output) and 25

(signal ground).

Note the data signal strength and “Induction Power Low” LED. If more than 1/2 of the signal strength

LED’s on the front panel are illuminated, and the Induction Power LED is not illuminated, then you will

have acceptable power and data transfer. It is highly recommended to optimize the RF tuning via the

jumpers in the tuning enclosure (see manual or “AT-4500 Tuning Enclosure Capacitance to Jumper

Setting” document).