Enraf Nonius 1403773, Руководство по обслуживанию

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No: SI 670 - 02 Oct. 1998 Page 1 of 2
Enraf-Nonius B. V.
P.O. Box 810
2600 AV Delft
The Netherlands
Service Information
Curapuls 670, Heat sink mounting.
This service information sheet describes how to improve the thermal contact of the main PC Board
heatsink to the chassis of the Curapuls 670.
The new type main PC Board (see also service information sheet SI 670 - 02) is equipped with an
heatsink which is directly mounted to the chassis of the unit.
The mounting of the main PC Board has been changed, the mounting hole in the heatsink at position
“A” is drilled through the heatsink.
Previous versions of the main PC Board are equipped with an mounting hole with internal M4 thread.
To improve the thermal contact the following modification is suggested:
- When replacing a (defective) main PC Board, the replacement Board must be mounted by
means of an longer screw, item “A” (M4 x 50 mm), to the chassis of the unit (see figure 1
at the other side of this service information sheet).
- Check the chassis before mounting the PC Board that a hole is drilled into the chassis at
position “A”, see figure 1.
- If there is no hole in the chassis at position “A”, drill a hole with a diameter of 4.5 mm. into
the chassis. (use the PC Board heatsink as a reference).
Caution: Make sure that no metal particles, caused by the drilling, will fall into the PC
Board or inside the housing. This could cause a short circuit.
- Mount the main PC Board to the chassis. Mount the heatsink firmly to the chassis with the
M4 x 50 mm. screw at position “A”.
The modification can also be made to an installed main PC Board to improve the thermal contact.
- Remove the mounting screw “A” (M4 x 10 mm.) and drill a hole through the heatsink and
the chassis.
- Mount the heatsink firmly to the chassis with the M4 x 50 mm. screw at position “A”.
Please add this service info to appendix C of your service manual.
Change classification
)
Perform immediately on all field units.
)
Perform routinely at next service call.
)
Perform only upon unit failure.
0
Information only
Commencing date: NA
Carried out from series: NA.
New components: Screw M4 x 50 mm. Qty. 1
Washer M4 Qty. 2
Spring washer M4 Qty. 1
Deleted components: NA
Our reference: WV 0167.113-70/02