F
OR
M
ODELS
: JGI, JGM, JGN, JGP
AND
JGQ
S
ECTION
4 L
UBRICATION
PAGE 4-47
Proflo PF1 - Using Pulse Output and Alarm Circuit at Same
Time:
If the control system needs to read both the block cycling, proximity switch, and the alarm
contact the following things must be taken into consideration.
1.
The Proflo PF1 has an on board processor and data acquisition system (DAQ).
The DAQ system records the time for each divider block cycle and stores this
data to EEPROM. The data is accessible and can be downloaded through the
Proflo infrared port to a Palm Operating System handheld computer with FFT
software. Therefore, it may not be necessary to have the control system read
and count the number of times the divider block cycles.
2.
If a PLC is used to read the pulse output, the PLC may be programmed to watch
for the divider block cycling and issue a shutdown if the block does not cycle for
a given time. This may eliminate the need to wire to both Proflo PF1 outputs and
save on field wiring connections.
3.
The Proflo PF1 alarm output, red wires, and the divider block cycle output, blue
wires, are not isolated from each other. If it is necessary to read both Proflo out-
puts, the isolation must take place on the equipment that is reading the contacts.
If the PLC input card is not isolated between channels both the alarm and pulse
outputs will act as the alarm contact. These contacts must also be isolated from
other inputs. See Figure 4-18
4.
If Isolated inputs are not an option, another way to achieve the output signal iso-
lation is to connect the alarm/shutdown contact to the safety system and install
another proximity switch for the control system to read and calculate oil con-
sumption. Refer to the “Proflo PF1 accessories” section below for a proximity
switch part number.
5.
If Isolated PLC inputs are not an option, yet another method of achieving isola-
tion between the Proflo PF1 outputs and the PLC is to wire the Proflo to the
"coil" side of a relay. Then use the contact side of the relay to the control system.
There are relays on the market that are very cost effective. Ariel recommends
using a solid state type relay for long life. See Figure 4-19
F
IGURE
4-18 E
XAMPLE
D
IAGRAM
TO
R
EAD
B
OTH
P
ULSE
& A
LARM
C
ONTACTS
Proflo
PF1
Ch 2
Ch 1
Power
Power
Input Card
Blue
GND
+V
Return
Return
Inputs must be isolated between channels
Red
Red
Blue
Optical
Iso
control
line
power
mosfets
Reverse
Polarity
circuits
Reverse
Polarity
circuits
power
mosfets
control
line
Mounted on Compressor,
Outputs are not isolated
Red
