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PRODUCT INSTALLATION MANUAL
2.7.1.
P
OWER
The HPTB boards provide redundant power connections, supply 1 and supply 2. Connect 24 VDC to the 2-
pin removable terminals on each HPTB. The connector is polarized, so you cannot insert it incorrectly. The
polarity is marked on the terminals. Both of these separate supply connections are reverse polarity
protected and then diode ORed to provide a single redundant power feed to the MUX. This common power
is also used to power the channels, and is connected through diodes to each group of 16 channels on the
HiSHPTB/32/TR-AI-01 and HiSHPTB/32/TR-AI-02 boards.
For the HiSHPTB/32/TR-AI-01-Y1 board, only the diodes for the supply power positive to each group of 16
channels are populated while the circuit common for all 32 channels are directly coupled together.
A series fuse protection is provided on each supply connection to avoid damaging the module in case of
accidentally reversing the polarity connection. In this case, the reverse voltage is clamped at –1.2 V and the
fuse blows. Restore correct supply polarity and replace the blown
properly sized, new fuse.
WARNING!
Improper supply connections can seriously damage the instrument and result in risk of fire
or explosion in hazardous locations!
DC SUPPLY REQUIREMENTS: The MUX is nominally rated for 24 VDC but will function from
approximately 20-30 VDC. The MUX draws a maximum of 100mA from the supply. If the power LEDs fail
to light check that the polarity of the supply line is correct.
WARNING!
Note that a crude, poorly filtered or unregulated supply can produce destructive (hundreds
of volts) voltage spikes during supply transformer switch-off transient. This could cause
minor problems to electro-mechanical components like relays or solenoids but will surely
degrade or destroy electronic equipment.
SUPPLY CONDUCTORS SIZING: Since these HIS boards supply power for the AI channels, a single unit
can normally require up to 2.56A and its conductors should be sized accordingly. Pepperl+Fuchs
recommends 14 AWG or larger wire be used to power this product.
2.7.2.
G
ROUNDING
The HPTB boards provide an earth terminal lug for connecting the various shield wires to earth. The shield
pins T, H, w, and FF for both J1 and J2 are directly connected to the earth terminal.
The HPTB boards also provide customer selectable capacitive coupling for the shielding associated with the
RS-485 communication to the MUX. Setting the cable shield to be directly coupled or capacitively coupled
is accomplished through jumper shunts. Placing the jumper shunt at JP1 across the pins will bypass the
capacitor and direct couple the corresponding shield to earth. For best practice any shield should be direct
coupled at one end of the circuit.
The HiSHPTB/32/TR-AI-01 board contains a bi-directional transient suppression diode between circuit
common ground and earth ground. This diode helps protect the system from surge or other EMC related
disturbances between circuit common and earth, but normally should not be conducting. If deviations in the
values show and you notice the board is damaged or parts get hot, it is likely that your system has one or
more ground loops. Check your installation to eliminate ground loops.
Also included with the HPTB is a DIN rail mountable terminal block. Use of the terminal lug and terminal
block for earth grounding will provide the shortest path and best practice for grounding of the HPTB. A 10-
14 AWG cable should be secured between the terminal lug and DIN rail block which provides a single point
to properly ground field wiring cable shields. This terminal may not be necessary to use if best practice
grounding techniques are employed.
DOCT-B3K7
fuse.
Be certain to reinstall a good,
P
11
21
AGE
OF
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