Using the TELEFAST Wiring Accessory
Original instructions
About us
Introduction
The TELEFAST pre-wired system consists of connecting cables and interface sub-bases as shown below: 
1
BMEAHI0812 module 
2
BMXFTA••22 connecting cables 
3
Interface sub-base ABE7CPA31 
4
Shield bar 
5
Clamp
BMXFTA••22 Connecting Cables
The BMXFTA••22 cables are pre-assembled cord set, made up of:
The figure below shows the BMXFTA••22 cables: 
1
BMXFTB2020 Terminal block 
2
Cable shielding 
3
25-pin Sub-D connector 
L
Length according to the part number.
The cable comes in 2 different lengths:
The following table gives the characteristics of the BMXFTA••22 cables:
Characteristic
Value
Cable
Sheath material
PVC
LSZH status
No
Environmental
Operating temperature
-25...70 °C (-13...158 °F)
Connecting Sensors
Sensors may be connected to the ABE7CPA31 accessory as depicted in the Wiring Diagrams topic.
The distribution of analog channels on TELEFAST terminal blocks with the reference ABE7CPA31 are as follows:
TELEFAST terminal block number
BMEAHI0812 pin out
Signal type
TELEFAST terminal block number
BMEAHI0812 pin out
Signal type
1
NC
Ground
Supp 1
NC
+24 Vdc (sensor supply)
2
NC
Ground
Supp 2
NC
+24 Vdc (sensor supply)
3
NC
Ground
Supp 3
NC
0 Vdc (sensor supply)
4
NC
Ground
Supp 4
NC
0 Vdc (sensor supply)
100
NC
+IS0
116
NC
+IS4
101
NC
NC
117
NC
NC
102
3
+IC0
118
11
+IC4
103
4
0 V0
119
12
0 V4
104
NC
+IS1
120
NC
+IS5
105
NC
NC
121
NC
NC
106
5
+IC1
122
13
+IC5
107
6
0 V1
123
14
0 V5
108
NC
+IS2
124
NC
+IS6
109
NC
NC
125
NC
NC
110
7
+IC2
126
15
+IC6
111
8
0 V2
127
16
0 V6
112
NC
+IS3
128
NC
+IS7
113
NC
NC
129
NC
NC
114
9
+IC3
130
17
+IC7
115
10
0 V3
131
18
0 V7
+ICx: + pole current input for channel x
+ISx: - pole voltage or current input for channel x
COMx: Common pin for channel x
NC: Not Connected
NOTE: The grounding of cables is facilitated using the ABE7BV•0 wiring accessory.
BMEAHI0812 with 2-Wire or 4-Wire Transmitter, TELEFAST Connector with Power Supply
These examples illustrate how to connect the input module to a 2-wire or 4-wire transmitter using a TELEFAST wiring accessory and cable. The cable includes a 20-pin terminal block. 24 Vdc power is supplied to the 4-20 mA current loop:
NOTE: To provide 4-20 mA power to the current loop, connect only the ISx and the ICx pins on the TELEFAST wiring accessory ABE7CPA31. The 0Vx pins are not connected.
2-wire design: 
1
2-wire transmitter 
2
4-20 mA current loop, with arrows indicating direction of current flow 
3
24 Vdc power supply 
4
Protective ground 
5
Secondary HART master (hand-held)
4-wire design: 
1
4-wire transmitter 
2
4-20 mA current loop, with arrows indicating direction of current flow 
3
Field power supply 
4
Protective ground 
5
Secondary HART master (hand-held)
HART Network Cable Characteristics and Lengths
The HART Communication Foundation has developed documentation describing recommended types and diameters of cable for HART networks. This documentation also includes instructions on how to calculate maximum cable lengths for a HART network.
To obtain a copy of this documentation, visit the HART Communication Foundation website at www.hartcomm.org, and download the document FSK Physical Layer Specification (document number HFD_SPEC-054). HART network cable characteristics and lengths information can be found at section 7.5 of this document.
For a BMEAHI0812 HART analog input module that uses loop power provided by a TELEFAST ABE7CPA31 wiring accessory, the maximum cable length between the sensor and wiring accessory is limited by the following calculation (in addition to the maximum cable length limits recommended by the HART Communication Foundation:
ABE7CPA31
Maximum capacitance
0.206 μF
Maximum cable length
(0.206 μF) / (Capacitance/unit)
Maximum length if Cap/unit = 55pF/feet
3745 ft (1141 m)