Delta Tau 24E2A - Limit;Flag Voltage Level Resistor Packs; OPTO-Isolation Considerations

Accessory 24E2A
Limit/Flag Voltage Level Resistor Packs
The Acc-24E2A limit and flag circuits also give the flexibility to wire in standard 12V to 24V limits and
flags or wire in 5V level limits and flags on a channel basis. The default is set for the standard 12V to
24V inputs but if the resistor pack is added to the circuit, the card can read 5V inputs.
Channel Specific Resistor Packs
Channel 1 Channel 2 SIP Description
RP22 RP24
2.2KΩ
Reverse resistor pack for encoder loss feature (for differential
encoders only)
RP23 RP25
220Ω
Termination resistor to reduce ringing (not installed by default).
RP45 RP46
1KΩ
Install for 5V limits
UBUS Specific Resistor Packs
Resistor Pack SIP Description
RP5
220Ω
Terminator (not installed, only used for non-UBUS)
RP6
2.2KΩ
Pull Down for old MACRO CPU
Pull Up for UMAC Turbo and MACRO
OPTO-Isolation Considerations
As shipped from the factory, the Acc-24E2A obtains its power from the UMAC Backplane or UBUS.
Using this type of setup will defeat opto isolation since the analog ground plane will be tied directly to the
digital ground plane.
To optically isolate the analog ground plane from the digital ground plane, connect an external power
supply to one of the many AA+15V, AA-15V, and AAGND inputs on the Acc-24E2A terminal blocks or
DB connectors. Also, remove the E85, E87, and E88 jumpers to isolate the external power from the
UBUS power supplies.
D8
MBRS140T3
A+15V
+
C42
22UF
25V
"AGND" PLANE
E88
D7
MBRS140T3
TP5
A-14V
L2
56uh
D9
1SMC18AT3
E88
2
1
AA+15V
A-14V
+
C3
22UF
25V
+
C43
22UF
25V
D2
MBRS140T3
AGND
AA+5V
VR1
LM7805T
(TO-220)
1
2
3
IN
GND
OUT
(ON HEATSINK)
AA-15V
E87
2
1
C45
1UF
50V
E85
2
1
D14
1SMC18AT3
+
C44
22UF
25V
D3
MBRS140T3
TP3
AAGND
TP6
A+14V
L1
56uh
+
C4
22UF
25V
E85
A-15V
A+14V
+
C2
22UF
25V
+
C5
22UF
25V
TP4
AA+5V
E87
R42
18 OHM
2.25W
AAGND
AAGND
Hardware Setup 9