Emerson E2 - Manual (Page 32)

2-8 • E2 RX/BX/CX I&O Manual 026-1610 Rev 13 14-SEP-2011
The PAK can control up to 4 condenser fan groups
containing up to 8 total condenser fans. The PAK con-
denser control strategy is sequential TD control with set-
point/deadband using ON and OFF delays.
The PAK has a compressor/condenser interlock fea-
ture that will override TD control and force the condenser
fans to stage off using the TD control OFF delay when all
compressors are off. This feature can be disabled with an
Enable/Disable setpoint or when the discharge pressure is
above a configurable setpoint.
The MultiFlex PAK boards consist of two circuit
boards: a bottom layer with 16 combination digital/analog
inputs, and a plug-in top layer which contains a combina-
tion of 8 relay outputs and 4 digital DC voltage outputs.
The analog outputs on the Multiflex PAK drive solid
state relays to control the fan stages. The relays control the
compressor groups.
The communication interface is RS485 I/O using the
Standard Extended Address Form for Retail Solutions Dis-
tributed Controllers. Currently, the PAK is designed to
interface with the Retail Solutions E2 controller.
2.2.3 The MultiFlex ESR Board
The MultiFlex ESR Valve Regulator board (P/N 810-
3199), shown in Figure 2-1, is an RS485 I/O Network
electronic stepper valve regulator capable of driving up to
eight stepper motor valves, which are typically used to
control temperature.
The MultiFlex ESR uses suction side variable-position
evaporator regulators (ESRs) to vary evaporator pressure
for an entire circuit and is an alternative to mechanical
EPR control.
The MultiFlex ESR receives input data from a Retail
Solutions E2 controller (via the I/O Network) and then
regulates the stepper valves according to the data from the
E2.
Each MultiFlex ESR board requires a Class 2, 80VA
24VAC center-tapped transformer for power. Retail Solu-
tions transformer (P/N 640-0080) is a multi-tapped pri-
mary transformer that may be used with the MultiFlex
ESR board.
2.2.4 Hand-held Terminal (P/N
814-3110)
The Hand-held Terminal (HHT) is used by manufac-
turers and service technicians to diagnose and test several
of Retail Solutions' existing and legacy products. The
HHT can be used on any Retail Solutions product with an
RJ-11 connector. The most common applications include:
• All MultiFlex I/O boards and the 8ROSMT
• All Gateway boards
• Stand-alone MultiFlex boards (RTU, RCB, PAK,
CUB)
LEGEND
1 INPUT POWER
(24VAC) 9 RS485 TERMINATION
JUMPERS
2 RS485 I/O NETWORK 10 HAND-HELD
TERMINAL JACK
3 PAK INPUTS 1-8 11 RELAY OUTPUT
CONNECTORS
4 PAK INPUTS 9-16 12 RELAY OUTPUT FUSES
(2A rated, 250V slow-
blow)
5 NETWORK ID DIP
SWITCH (S3) 13 RELAY STATUS LEDs
6 INPUT TYPE DIP
SWITCHES (S1, S2) 14 RELAY FAIL-SAFE
SWITCHES
7 BOARD STATUS LEDs
(Code A, Code B, General
Status) 15 PAK ANALOG
OUTPUTS 1-4
8 DC POWER OUTPUTS
(3 at +5VDC, 1 at
+12VDC) 16 NETWORK STATUS
LEDs
Table 2-9 - MultiFlex PAK
Figure 2-1 - MultiFlex ESR Board Layout
8
3
7
24VAC CT 75 VAC Power Input
Valve Connectors (8)
I/O Network Input
Termination Jumpers
Network Address Switches General Status LED
1
5
2
3
4
6
7
8
HHT Jack
TX and RX LEDs
9
10
Open LED (8)
Close LED (8)
9
10