7
INDEX and DOWN ARROW: Pressing these
keys simultaneously will allow backing up one menu
item, or if at the rst menu item they will cause the display
to return to the primary menu. If an alarm condition has
occurred, these keys may be used to reset the alarm.
INDEX and ENTER: Pressing these keys
simultaneously and holding them for 5 seconds allows
recovery from the various error messages. The following
menu items will be reset:
ALiH: Alarm inhibit
CHEC CAL: Check calibration error
Correct the problems associated with the above
conditions before using these reset keys. More than one
error could be present. Caution is advised since several
items are reset at one time.
The Home Display
The home display is the normal display while the control
is operating. If no errors or functions are active, the
HOME display will indicate the Process Variable (the
level that is being measured) on the top display and the
SP1H value, Pump 1 On Set Point, on the bottom display.
Error messages may over-ride the HOME display. See
ERROR MESSAGES on page 12.
While in the Secondary Menu, if no key is pressed for
a period of 30 seconds, the display will return to the
HOME position displaying the process value. While in
the Secure Menu, if no key is pressed for a period of
60 seconds, the display will return to the HOME position
displaying the process value. Outputs are disabled
(turned off) when the Secure Menu is active.
Security Level Selection
Three levels of security are provided. The SECr menu
item security level may be viewed or changed at any time
regardless of the present security level in the Secure
menu. The display shows the current security level. To
change security levels change the password value using
the UP ARROW or DOWN ARROW keys and
pressing the ENTER key. Refer to the password
table (following) for the correct value to enter for the
security level desired.
To set the access level to, for example, 2, at the SECr
menu item press the UP ARROW key until the upper
display shows the password, 1101. Press the ENTER
key. The display will blink, and return with the level value,
2, in the upper display.
The password values shown in the table cannot
be altered. Retain a copy of these pages for future
reference. This is the only reference made to password
values in this instruction book.
LEAD/LAG OPERATION
The Mercoid® MPCJR pump controller is designed
to easily operate a pair of pumps in the most efcient
manner possible. The controller has a ‘lead/lag’ feature
that allows two pumps to operate in an alternating
fashion to minimize wear.
The Mercoid® MPCJR pump controller has a pair of
set points each for pump 1 and pump 2. If the lead/lag
feature is turned off, SP1H and SP1L control pump 1 and SP2H
and SP2L control pump 2. If the lead/lag feature is turned
on, pumps 1 and 2 will be controlled in the alternating
fashion described below. In all cases the P1 lamp will
indicate activity of pump 1 and the P2 lamp will indicate
activity of pump 2. The lead/lag operation is set in the
Secure menu with the item LdLg.
Lead/Lag On
After installation, set the SP1H to the high level (pump on
point) for standard operation. Set SP1Lto the low level
(pump off point). Set the SP2H to the level where you want
BOTH pumps to turn on (emergency pump on). Set the
SP2L to the level where you want the second pump to turn
off (emergency pump off).
The controller will not allow you to set SP1H below SP1L,
SP1L above SP1H, SP2H below SP2L, or SP2L above SP2H. The
controller will not allow you to set any set point or alarm
point above or below the programmed scale. No error
messages are generated. The displayed value will stop
at an allowable point just above (or below, as the case
may be) the maximum or minimum allowed.
In normal operation, when the SP1H point is reached, one
of the pumps will turn on. When lead/lag is turned on,
pumps 1 and 2 will alternate. If the level reaches the SP2H
point, both pumps will be turned on until the SP2L point is
reached, where one of the pumps will turn off. When SP1L
is reached, remaining running pump will turn off. The last
pump off will not be the next pump on.
Lead/Lag Off
If lead/lag is turned off, SP1H and SP1L control pump 1 and
SP2H and SP2L control pump 2. There is no alternating
function.
OPERATION RV, RC ISOLATED ANALOG
RETRANSMISSION
The analog retransmission option allows the Process
Variable or the Set Variable to be sent as an analog
signal to an external device. The signal may be either
0-10 VDC (option RV) or 0 (or 4)-20 mA DC (option RC).
The output may be changed in the eld from one to the
other by the toggle switch located on the top printed
circuit board.
Wire the output as shown on page 3.
To set up the analog retransmission, rst determine the
scale range that the analog signal will represent. The
maximum scale is 9999 counts. In the Secondary Menu
set POL for the the scale value that will be represented by
the low end of the analog signal (0 V or 0 mA). Set POH for
the scale value that will be represented by the high end
of the analog signal (10 V or 20 mA).
If you require a suppressed scale or output, you may use
the following equations to determine the proper settings
for POL and POH.
K= (Highest desired scale reading - Lowest desired
scale reading)/(Maximum desired analog signal -
Minimum desired analog signal).
POH= ((Maximum possible analog output - Maximum
desired analog signal) *K) + Highest desired
analog reading.
POL = Lowest desired scale reading - ((Minimum desired
analog output) *K).
Operation is automatic. There are no further programming
steps required.
PASSWORD TABLE
Menu
Security
Level
Status
Displayed
Value
When Viewed
Password
Value To
Enter
Secondary
Secure
Secondary
Secure
Secondary
Secure
Locked
Locked
Unlocked
Locked
Unlocked
Unlocked
2
3
4
1101
1011
111
