Make sure that the platesetter has not been working for the previous 45
minutes.
Make sure the drum vacuum holes are opened and that the customer cleans
them properly (penetrates at least 1 inch deep).
Use vacuum gauge by ACCU-AIRE with resolution of 0.02 bar, P/N 344C03012
(this gauge has been tested for accuracy).
Test is performed with no plate on drum.
Connect the vacuum gauge tube to the drum vacuum nipple below the swivel
joint (see picture below).
Activate the vacuum pump and make sure the tube is connected correctly and
that it does not leak.
Vacuum pressure should be read at least 2 minutes after pump has
been started and when the dial reading is stable. Make sure that the dial
is VERTICAL.
Vacuum pressure should be:
0.35 bars (10.3 inches Of mercury) minimum for U 3.40 SA
pumps (with oil).
0.23 bars (6.8 inches Of mercury) minimum for VT 4.40
pumps (dry).
Should the vacuum readings fail to conform to these specifications, check:
All tubes and connections going from pump to drum. Check for leaks,
bad connections, cracked tubes or leaking swivel.
Pump performance.
- Check pump filter.
- Measure supply voltage (on connector to the pump) at distribution box.
Voltage should be 208V (phase to phase).
If these conditions are met, then you will need to change the pump.
If reading is above 0.44 (13 inches of mercury) bars (U 3.40
SA and VT 4.40), clean the drum holes or check for any other clogging
in the system.
Stop the vacuum pump, disconnect the vacuum gauge and reconnect the vacuum
detector tube to the nipple.
