Thermal Dynamics MERLIN 6000, Руководство по обслуживанию, Страница: 47 / 112

Manual 0-2569 41 SERVICE TROUBLESHOOTING
Wire
#96A
Pilot Resistor
R16
Clamp
Clamp
A-01853
Wire
#150
Pilot Resistor
R21
Pilot Resistor
R22
Wire
#74
Wire #99
Wire
#96
Temp
Switch
Figure 4-4 Location Of Pilot Resistors (Viewed
From The Front Of Power Supply)
3. Check the busbar configuration on the input ter-
minal board to determine which range the power
transformer is set for.
4. Measure the level of the AC line voltage being sup-
plied to the Power Supply.
5. To determine the recommended pilot resistor set-
ting use the following table as follows:
a. Locate the transformer voltage range (200-230V,
380-460V or 500-575V)
b. Find the voltage that is nearest what was mea-
sured above.
c. Note the ohms value for the voltage. Example:
If the transformer range is 380-460, and the
measured voltage is 455, then the pilot resistor
value is 6 ohms.
NOTE
Voltages that are from 200 to 210V, 410 to 420V
and 510 to 520V required values from 8.5 or 9 to
4.5 ohms. If the voltage is near one of these points
it is best to set for the lower ohms value.
The reason is because within each range the Power
Supply will automatically select a high or low tap
on the transformer secondary. This is based on
the input AC line voltage at the time the Power
Supply is turned ON. If the line voltage is near
one of these points the voltage might measure, for
example, 410 VAC and the pilot resistor setting
should be 9 ohms to have a good pilot. The next
time the system is turned ON, the input AC line
voltage may have gone up to 420VAC causing the
pilot to sputter because 420VAC requires setting
of 4.5 ohms.
Pilot Resistor Setting vs. Input Line Voltage
Transformer Voltage Range
200-230 VAC 380-460 VAC 500-575 VAC
Input
(VAC)
Ohms
Input
(VAC)
Ohms
Input
(VAC)
Ohms
180 6.5 340 5 450 5.5
190 7.5 350 5.5 460 6
200 8.5 360 6 470 6.5
210 4.5 370 6.75 480 7
220 5.5 380 7.25 490 7.5
230 6.5 390 8 500 8
240 7.5 400 8.5 510 8.5
250 9 410 9 520 4.5
420 4.5 530 5
430 5 540 5.5
440 5.5 550 6
450 6 560 6.5
460 6.5 570 7
470 7 580 7.25
480 7.5 590 7.5
490 8 600 8
500 8.5 610 8.25
510 9 620 8.5
630 9
6. Wires are attached to the pilot resistors with metal
clamps or taps. Locate and loosen the screw that
secures the wire #99 tap on resistor R16. Deter-
mine, from the Figure below, the correct position
for the tap on R16 and tighten the screw.
Example:
To set for 6 ohms measure 5” from the right side
of R16, where wire # 96 attaches, and secure the
#99 tap at that position.