Measurement Computing DAC488 v.1 - Manual (Page 22)

16 DAC488 Power & Assembly DAC488 User’s Manual
Fuse Replacement
CAUTION CAUTION CAUTION CAUTION
Service: This product contains no operator serviceable parts, or operator replaceable
parts within the case. Fuse replacement and the changing of selected line voltage must
be performed by qualified service personnel. Never open the DAC488 case while it is
connected to the AC line, or when analog output terminals are connected to a device
exceeding 60 VDC or 30 Vrms common mode voltage. Contact with voltage potentials
could cause bodily injury or death!
The DAC488 unit contains an internal AC line fuse. The fuse is located next to the internal line-voltage
switch (S104). You may replace the fuse by using the procedures found in the following text.
Note: If disassembly or disconnections are necessary, first turn off the power, then disconnect the analog
output cables, next disconnect the AC power line, and then any other cables, prior to disassembly.
To Replace the Fuse
1. Turn off the power, then disconnect the analog output cables. Next, disconnect the AC power line
cord, and then all other cables from the unit.
2. Place the unit on a flat surface. Remove the six screws on top of the case and remove the top cover.
3. Located next to the line-voltage selection switch (labelled S104) is the power fuse. Gently pull upward
on the plastic fuse housing. The entire housing with the fuse inside should be removed.
4. Open the fuse housing by pushing up on the tab on the bottom of the housing. Remove the fuse, and
replace it with the proper type using the following list as a guide:
•
For line voltage 105-125 V, use fuse type 3/4 A, Slo Blo, 3AG
•
For line voltage 210-250 V, use fuse type 3/8 A, Slo Blo, 3AG
CAUTION CAUTION CAUTION CAUTION
Fuse Failure: Fuse failure indicates a possible problem within the device circuitry. If a
fuse blows, contact a qualified service representative. Replacement fuses are to be
installed by qualified service personnel with the unit disconnected from the power
source and with all other terminals disconnected. If the line voltage selector is
changed, then the fuse designated for that line voltage must be used.
5. Close the housing. Insert the fuse into the fuse holder.
6. Make note of the new fuse rating for later reference. If you have also changed the operating line-
voltage selection, return to the previous section Line Voltage Selection – Step 5.
7. Carefully reassemble the unit.
Note: For re-assembly, first reconnect the AC power line, next reconnect the analog output terminals, and
then any other cables, prior to reapplying power to the entire system.