Internal Controller Board Trouble; Timed Ventilation Problem; No Power; Lcd Display Unreadable - Macurco DVP-120C User Instructions

Macurco DVP-120C Manual
removing power from the sensor – causing the loop current to go to zero, or by completely removing power from
the DVP-120C.

6.1.2 Internal Controller board Trouble

If the sensor status display and investigative efforts reveal no problems with the input channel current loops and
channel configuration, the most likely trouble condition is an internal problem detected by the DVP-120 controller.
In this case, contact the Macurco Technical Support at 1-844-325-3050 for advice and help.

6.2 Timed Ventilation Problem

When using the timed ventilation mode, the system clock should be checked regularly (at least twice a year). The
battery-backed real time clock in the DVP-120 does not adjust for daylight saving time so the spring and fall switch
over points are good choices to check the system clock.
Use only for monitoring the gases which the sensors and equipment are designed to
detect. Failure to do so may result in exposures to gases not detectable and result in
serious injury or death. For proper use, see supervisor or User manual, or Contact
Technical Support at 1-844-325-3050.

6.3 No Power

The DVP-120C starts up as soon as power is applied to the microcontroller, and the DVP-120C is designed to have
power continuously applied to the unit. An external indication of successful power application to the unit is the
immediate operation of the Status Lamps grouped around the LCD. If the operator does not see an immediate
response from the status lamps, power should be checked at AC~.
If the correct voltage is noted at AC~, then the internal fuse of the DVP-120C should be investigated. The DVP-120C
is protected from over-current and transient situations by the fuse at F3. After removing power from the DVP-120C,
F3 can be checked by removing the safety cover. If necessary, replace F3 with a 5x20 mm SLO-BLO fuse with a rating
of 1 Amp 250V, e.g. Littelfuse P/N 218001. Be sure to Replace the Safety Cover on F3 before re-applying power to
the DVP-120C.

6.4 LCD Display Unreadable

It is possible that the LCD is unreadable due to temperature or aging of the control panel. If this is the case the
following steps should rectify the problem:
• Hold the MENU key for three (3) seconds. After three seconds, the power led will turn red. After two
additional seconds, the LCD backlight will also be turned off.
• Press the UP and DOWN cursor keys to change the LCD contrast. Each press of the UP or DOWN cursor
key will change the contrast by a step in that direction. Adjust the contrast for best viewing.
• Press any other key to exit the contrast-setting mode.
REV – 1.0
WARNING
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