FCI ST50 - Hardware Verification; Fuse and Cable Seating Checks

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ST50 Mass Flow Meter Fluid Components International LLC
Hardware Verification
Equipment Required:
• Digital Multimeter
• Screwdriver
The ST50 flow meter is made up of these basic components:
• Sensor element
• Customer interface circuit board
• Control circuit assembly circuit board module
• Electronics enclosure
Step 1
Verify fuse (F1) located on the customer interface circuit board is in normal working condition.
Remove power from the instrument. Open the electronics enclosure exposing the customer interface circuit board. This circuit board is
located under the shorter enclosure lid along with all of the power and input/output connections. Unscrew the clear cover on the fuse
and pull the fuse out of the fuse holder. Check the fuse for continuity. If fuse reads open, replace with equivalent component (FCI part
no. 019933-01), Wickmann Inc. series 374, 1.6 A (amp code 1160), package 0410 (short radial leads).
Step 2
Verify interconnecting cable from the customer interface board and the control circuit board assembly module are correctly seated into
the appropriate header.
Remove power from the instrument. Open the electronics enclosure exposing the customer interface circuit board. This circuit board is
located under the shorter enclosure lid along with all of the power and input/output connections. Remove the 2 screws securing the
interface circuit board to the electronics enclosure. Carefully lift the interface face board exposing the interconnecting cable between
the interface board and the control circuit assembly. Verify cable is seated firmly at both ends of the cable header.
Fuse (F1)
Cable Header
Interface Board
Control Circuit
Assembly
AC power customer interface board shown.
Fuse (F1) on DC power customer interface
circuit board located in similar position.