BenQ Projector HT1085ST User Manual

  51
  Maintenance
Timing of replacing the lamp
When the Lamp indicator lights up red or a message appears suggesting it is time to replace the lamp, 
please install a new lamp or consult your dealer. An old lamp may cause a malfunction in the projector 
and in some instances the lamp may explode. Go to http://www.BenQ.com for a replacement lamp.
The Lamp indicator light and Temperature warning light will light up if the lamp becomes too hot. Turn 
the power off and let the projector cool for 45 minutes....

52 Maintenance  
Replacing the lamp
•  To reduce the risk of electrical shock, always turn the projector off and disconnect the power cable 
before changing the lamp.
•  To reduce the risk of severe burns, allow the projector to cool for at least 45 minutes before replacing the 
lamp.
•  To reduce the risk of injuries to fingers and damage to internal components, use caution when removing 
lamp glass that has shattered into sharp pieces.
•  To reduce the risk of injuries to fingers and/or compromising...

  53
  Maintenance
7. As shown in the illustration, lower the new lamp.
8. Tighten the screw that secures the lamp.
9. Ensure the handle is fully laid flat and locked in place.
•  Loose screw may cause a bad connection, which could result in 
malfunction.
•  Do not over tighten the screw.
10. Replace the lamp cover on the projector.
11. Tighten the screw that secures the lamp cover. 
•  Loose screw may cause a bad connection, which could result in 
malfunction.
•  Do not over tighten the screw.
12....

54 Maintenance  
Indicators
There are three indicators which show the status of the projector. Check the following information 
about the indicator lights. If there is anything wrong, turn the projector off and contact your dealer.
•  When the projector is in a normal state
•  When the projector is in an abnormal state
Status & Description
Orange Off OffStand-by mode
Green
FlashingOff OffPowering up
Green Off OffNormal operation
Orange
FlashingOff Off
•  The projector needs 90 seconds to cool down as it...

  55
  Maintenance
Troubleshooting
ProblemCauseRemedy
The projector does 
not turn on.There is no power from the power 
cable.Plug the power cable into the AC inlet on the 
rear of the projector, and plug the power 
cable into to the power outlet. If the power 
outlet has a switch, make sure that it is 
switched on.
Attempting to turn the projector on 
again during the cooling process.Wait until the cooling down process has 
completed.
The lamp cover is not securely 
attached.Correctly attach the lamp...

56 Maintenance  
Specifications
Projector specifications
All specifications are subject to change without notice. 
Optical
Resolution
1920 (H) x 1080 (V)
Display system
Single-chip DLP
TM system
Lens F/Number
F = 2.59 to 2.87, f = 16.88 to 21.88 mm 
(HT1075) 
F = 2.6 to 2.78, f = 10.2 to 12.24 mm
(HT1085ST)
Lamp
240 W lamp
Electrical
Power supply
AC100–240V, 3.5 A, 50-60 Hz (Automatic)
Power consumption
375 W (Max); < 0.5 W (Standby)
Mechanical
Weight
2.75 Kg (6.06 lbs) (HT1075)
2.85 Kg (6.28 lbs)...

  57
  Maintenance
Dimensions
311.87 mm x 244.12 mm x 104 mm (W x D x H)
Ceiling mount installation
Unit: mm 244.12311.87
104
625.95
577.7
537.9
95.33
163.12
244.12 102.97      
43.55
311.95
137
160
46.21 115
80
Ceiling mount screws: M4 
(Max. L = 25 mm; Min. L= 20 mm)
Unit: mm 

58 Maintenance  
Timing chart
Supported timing for PC input
FormatResolutionRefresh rate 
(Hz)H. Frequency 
(KHz)Pixel 
Frequency 
(MHz)
720 x 400 720 x 400_70 70.087 31.469 28.3221
640 x 480VGA_60* 59.940 31.469  25.175 
VGA_72 72.809 37.861  31.500 
VGA_75 75.000 37.500  31.500 
VGA_85 85.008 43.269  36.000 
800 x 600SVGA_60* 60.317 37.879  40.000 
SVGA_72 72.188 48.077  50.000 
SVGA_75 75.000 46.875  49.500 
SVGA_85 85.061 53.674  56.250 
SVGA_120** 
(Reduce Blanking)119.854 77.425 83.000
1024 x...

  59
  Maintenance *Supported timing for 3D signal with Frame Sequential, Top-Bottom and Side-by-Side format.
**Supported timing for 3D signal with Frame Sequential format.
***Supported timing for 3D signal with Top-Bottom and Side-by-Side format.
The timings showing above may not be supported due to EDID file and VGA graphic card limitations. It is 
possible that some timings cannot be chosen.1280 x 1024SXGA_60*** 60.020 63.981 108.000 
SXGA_75 75.025 79.976 135.000
SXGA_85 85.024 91.146 157.500
1280 x...

60 Maintenance  
Supported timing for HDMI (HDCP) input
FormatResolutionRefresh rate 
(Hz)H. Frequency 
(KHz)Pixel 
Frequency 
(MHz)
640 x 480VGA_60* 59.940 31.469 25.175 
VGA_72 72.809 37.861 31.500 
VGA_75 75.000 37.500 31.500 
VGA_85 85.008 43.269 36.000 
720 x 400 720 x 400_70 70.087 31.469 28.3221
800 x 600SVGA_60* 60.317 37.879 40.000 
SVGA_72 72.188 48.077 50.000 
SVGA_75 75.000 46.875 49.500 
SVGA_85 85.061 53.674 56.250 
SVGA_120** 
(Reduce Blanking)119.854 77.425 83.000
1024 x 768XGA_60* 60.004...