Connections – Rs232 / Net Web; Desiccant Service; Valve Service; Jumper J2 – Unused - Gardner Denver DGH Series Instruction Manual

switch to stop a dryer. Closing this switch will affect
the same response as a loss of power. Both inlet-
switching valves will open and both purge-
repressurization valves will close. A tower that is
actively purging when the power on/off button is
actuated will be subjected to a rapid repressurization
that can lead to fluidization and subsequent abrasion
of the desiccant bed. Ideally, dryers should only be
powered off during those portions of the drying cycle
when both desiccant towers are at full operating
pressure. Use of the remote start/stop connections as
described in Section 6.2.3 would be preferable in most
cases.
•
Terminals J2-7 and –8 (remote alarm reset and manual
cycle increment switch)
6.2.5 Connections – RS232 / Net Web
RS232 and/or Net Web connections can be made at the 3-pin
connector labeled J5 and located at the upper left-hand corner
of the control board. A cable for this connection can be
purchased through your distributor.
6.3 Control Board Jumpers – Level 1
Refer to Figure 6-3, Point to Point Connection Diagram – Level 1
Controller. In the upper left hand corner of the control board
there are four two-pin jumpers labeled J1 through J4. Only three
of the four jumper pairs are utilized. Pair J2 is not used. The
jumper is a removable bridge that is used to make or break
continuity between the two pins that form a pair. When installed
in the ON position, the jumper is placed on both pins of the pair
and continuity between the pins is established. When installed
in the OFF position, the jumper is removed or stored on a single
pin and continuity is broken. Jumper functions are as follows:
6.3.1 Jumper J1 – Maximum Operating Pressure
Jumper J1 is used to select the maximum operating pressure.
Installed in the OFF position when operating at inlet pressures
of 60 to 150 psig (4.2 to 10.5 kgf/cm
position when operating at inlet pressures of 120 to 250 psig
(8.4 to 17.6 kgf/cm ). This setting will affect tower purge and
2
repressurization times. (Refer to serial number tag.)
6.3.2 Jumper J2 – Unused.
6.3.3 Jumper J3 – Service Reminder Interval
Jumper J3 is used to select the service reminder interval.
Installed in the OFF position when the Normal service reminder
interval is desired. Installed in the ON position when the Severe
service reminder interval is desired. Service items, check points
and time intervals appear in Table 6-2.
6.3.3.1 Filter Service
When the service interval for filters has expired the following
LEDs will blink:
•
Service LED (amber)
•
Three filter LEDs (amber)
). Installed in the ON
2
- 17 –

6.3.3.2 Desiccant Service

When the service interval for desiccant has expired, the
following LEDs will blink:
•
Service LED (amber)
•
Both tower regenerating LEDs (amber). The service
function overrides the normal display of the tower
regenerating LEDs.

6.3.3.3 Valve Service

When the service interval for valves has expired, the following
LEDs will blink:
•
Service LED (amber)
•
Four valve LEDs (green) The service function overrides
the normal display of the valve LEDs.
To extinguish the blinking LEDs and restart the timer for a new
service interval, press the alarm reset button. NOTE: Time
continues to accumulate as long as power is supplied to
the controller, whether the controller is switched on or off.
Use the following sequence to manually reset the accumulated
service interval time for all timers.
•
Pause for about 1 second at each instruction. If the
sequence is executed too quickly it will not work.
•
With the controller already on, press and hold the alarm
reset button.
•
Press and hold the on/off button.
•
Release the on/off button.
•
Release the alarm reset button. The service interval time
is now reset; the maintenance LED flashes three times to
acknowledge the action.
Service Item
(Customer check points
are listed for each item)
Filters
1. Check prefilter Delta-P
2. Ensure prefilter drain is discharging
3. Check afterfilter Delta-P
Desiccant
1. Check moisture indicator
2. Check dryer outlet dew point
3. Inspect mufflers for excessive dusting
Valves
1. Ensure valves are cycling properly
2. Check for switching failure alarms
3. Inspect valves for leaks - adjust purge
valve as needed
Table 6-2
Jumper J3 – Service Reminder Intervals
6.3.4 Jumper J4 – Power Recovery Mode
Jumper J4 is used to select the power recovery mode. When
power to the controller is interrupted, the position of this jumper
controls the recovery mode of the dryer when power is restored.
Installed in the OFF position when automatic power recovery is
6. Controller – Level 1
Normal Severe
Service Service
Interval Interval
(J3 OFF) (J3 ON)
4,000 2,000
Hours Hours
8,000 4,000
Hours Hours
4,000 2,000
Hours Hours
6. Controller – Level 1