Sensoray 2426 - Manual (Page 6)

2426 Instruction Manual 4 Power
Chapter 3: Power
3.1 Terminal Block
A pluggable terminal block (connector “TB” in Figure 2) is
used to connect power to the module.
The pin names shown in Table 2 are silkscreened onto the
module for easy identification.
3.2 Module Power
An external 24VDC power supply must be connected to the TB
to supply operating power to the module. Module operating
power may be applied across any TB pins labeled +24V and
GND.
The TB has two GND pins and two +24V pins; these are
duplicate connections (i.e., both +24VDC pins are electrically
shorted together, as are both GND pins) that may be used to
route the applied 24VDC module input power back out to
external loads in daisy chain fashion.
PWR lights continuously when 24VDC power is correctly
applied to the module and the module’s internal 3.3V
DC-DC converter is operating normally.
3.3 Auxiliary/Interlock Power
In addition to the required 24VDC supply, up to five auxiliary
DC power supplies may be connected to the TB on circuits
labeled PWR1 to PWR5. All of these power sources are
optional; none are required for module operation. If any of
these circuits are not used, simply leave the associated TB pins
disconnected.
All auxiliary power supplies must be positive with respect to
the module’s power supply GND. Also, the returns of all
auxiliary power supplies must be connected together and to the
module’s 24VDC operating power return.
3.3.1 Internal Power Bus
All of the module’s power input signals—including +24V
module power, PWR1 through PWR5, and GND (which is
common to all power input signals)—comprise the module’s
internal power bus. The power bus is routed to the Interlock
Power Routing Matrix (see Figure 2) so that any signal on the
power bus can supply power to any digital output channel.
Power sources connected to PWR1 through PWR5 may be
routed through interlock contacts, and they may have output
voltages less than +24VDC. These auxiliary circuits are used
to connect alternative power sources to specific digital output
channels in cases where such channels require:
• Positive DC operating voltage less than +24V (e.g., +5V,
+12V).
• Interruptible DC operating voltage (i.e., interlocked), to
guarantee fail-safe shutdown.
3.4 5VDC Output
The TB pin labeled “+5VOUT” brings out +5V power from the
module’s internal DC-DC converter. This may be used to
supply 5VDC power to external loads.
Table 1: Terminal Block Pin Assignments
Pin Name Function
1, 2 GND
Return for the +24VDC power supply that is
connected to pin 3 or 4. One of these must be
connected to the 24VDC power supply return, while
the other may be used to route incoming GND out to
an external load.
3, 4 +24V
+24VDC operating power for the 2426 module. One
of these pins must be connected to the +24V supply,
while the other may be used to route incoming +24V
out to an external load.
5 PWR1 Optional positive DC power #1, referenced to GND.
6 PWR2 Optional positive DC power #2, referenced to GND.
7 PWR3 Optional positive DC power #3, referenced to GND.
8 PWR4 Optional positive DC power #4, referenced to GND.
9 PWR5 Optional positive DC power #5, referenced to GND.
10 +5VOUT
+5V output from module’s internal DC-DC
converter, referenced to GND. This may be used to
supply a modest amount of power to external 5VDC
loads.