144
ZM400 Series Indicators Service Manual
13.8 STVS (Severe Transient Voltage Suppressor) installation
Mounting studs
for the STVS
module.
STVS module on
mounting studs (not
secured by screws)
Attach incoming scale
interface lines to the IN
side of the STVS module.
The STVS kit is used to suppress high voltages before they can damage the components of the indicator. Use these
instructions to install the STVS module.
1.
Disconnect the indicator from power.
2.
Remove the acorn nuts from the back panel and carefully remove the back. Be sure not to stretch or
damage the ground wire connected to the inside of the back panel.
3.
There are four studs on the inside the back cover. Mount the STVS module to the studs as shown in the
photos below. Use the supplied screws. The module should be turned horizontally on the back plate with
the IN marked connector positioned away from the Gore
®
Vent. The OUT side is turned toward TB1. See
the photos below.
4,
Attach the scale interface wires to the IN side of the module per the wiring illustration
shown below.
5.
Use wires of adequate length and connect the OUT side of the STVS module to TB1 on
the indicator main board, per the illustration below.
6.
Be sure no wires or cables are pinched between the front and back of the indicator as
you replace the back panel. Tighten the acorn nuts in the proper fashion.
TB1
IN
side
1
234567
1
234
5
67
Scale Interface Cable
-EXC
+EXC
-SEN
+SEN
-SIG
+SIG
-SHIELD
WHT
WHT/ORG
RED
YEL
BLU
GRN
BLK
To TB1
+EXC
-SEN
+SEN
-SIG
+SIG
-SHIELD
WHT
WHT/ORG
RED
YEL
BLU
GRN
-EXC
IN side
BLK
