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SECTION 4 - MICROBOARD 031-02430-000 AND 031-02430-001
FORM 160.54-M1
ISSUE DATE: 10/25/2019
JOHNSON CONTROLS
JCI COMPANY CONFIDENTIAL
4
Medium Voltage Solid State Starter (MV SSS)
and Medium Voltage Variable Speed Drive
Interface (MV VSD)
These drives communicate with the microboard via
the COM2 RS-485 Modbus serial port (J13). COM2
serial port is selectable between RS-232 and RS-485
with Program Jumper JP17. It must be positioned on
pins 1 and 2 to select RS-485 serial port operation. See
and
Medium Voltage Solid
State Starter – Service (Form 160.00-M5) and Medium
Voltage Variable Speed Drive – Service (Form 160.00-
M6)
for details of this interface. Microboard (P/N 031-
02430-001) is required for these applications. Software
version C.OPT.01.15.xxx (or later) is required for MV
SSS. Software version C.OPT.01.16.xxx (or later) is
required for MV VSD. When the MV SSS or MV VSD
is selected on the SETUP Screen, the COM2 serial port
with Modbus protocol is automatically enabled. With
the MV VSD, the Adaptive capacity Control function-
ality is contained on the microboard.
Printer Interface
An optional printer can be connected to COM1 RS-232
serial data port (J2). TX data to the printer is at J2-
4. The DSR (Data Set Ready or busy) signal from the
printer is at J2-2. Signal levels are standard RS-232.
The microboard sends data to the printer at the selected
baud rate until the printer buffer becomes full, where-
upon the printer asserts its Busy signal. The microboard
suspends data transmission until the printer can accept
more data. Each printer must be setup/configured to
operate properly with the microboard. The Baud, Data
Bits, Parity and Stop Bits must be programmed on the
COMMS Screen. Other printer setup is performed on
the Printer Screen. Refer to
OptiView Control Panel –
Operation (Form 160.54-O1)
for details of available
printers and printer setup instructions.
E-Link Gateway Interface
An optional E-Link Gateway printed circuit board can
be connected to the COM 4B RS-232 serial data port
(J2). TX data to the E-Link Gateway is at J2-7. RX
data from the E-Link Gateway is at J2-6. Signal lev-
els are standard RS-232. The E-Link Gateway polls
system pressures, temperatures and status from the
microboard. It holds it for retrieval by third-party de-
vices. See
manual.
Digital inputs
The I/O Board converts the 115 VAC inputs to logic
level inputs for the microboard at J19. A 115 VAC input
to the I/O Board is converted to a logic low (less than
1 VDC). A 0 VAC input to the I/O Board is converted
to a logic high (greater than 4 VDC). See
of this manual for details of the I/O Board.
Digital Outputs
The microboard controls 115 VAC relays and solenoids
via the I/O Board (via J19). The I/O Board contains
+12 VDC relays that isolate the microboard low volt-
age circuits from the 115 VAC device coils. Solid state
switching devices are used to control the relays. The
microboard energizes the +12 VDC relays by applying
a ground to the coil input. They are de-energized by
opening the ground path. The contacts of these relays
switch 115 VAC to system relays and solenoids. The
outputs that control the chilled liquid pump and com-
pressor motor starter have anti-chatter (anti-recycle)
timers associated with them. The output that controls
relay K0 is not allowed to change at a rate greater than
once every 10 seconds. The output that controls relay
K13 is not allowed to change at a rate greater than once
every 20 seconds.
The microboard controls actuator motors via Triacs on
the I/O Board. Each actuator has an open winding and
a close winding. Current flowing through a winding
causes the actuator to rotate in the respective direction.
Each winding is controlled by a Triac. The Triac is
turned ON to allow current to flow through a winding.
The microboard turns on the Triac by applying a logic
low (less than 1 VDC) to the Triac driver on the I/O
Board. It turns it OFF by applying a logic high (greater
than 4 VDC). See
of this
manual for details of the I/O Board.
Analog Inputs
System pressures, in the form of analog DC voltages,
are input from Pressure Transducers. See
of this manual. Formulas
and graphs are included to calculate the expected trans-
ducer output voltage for a given pressure input.
System temperatures, in the form of analog DC volt-
ages, are input from thermistors. See
of this manual.
Included are tables to convert the expected output volt-
age for any temperature applied to the thermistor.
