D8 Series User’s Guide
Chapter 8: Specifications
157
1.5 in.
(37 mm)
4.0 in.
(102 mm)
6.4 in.
(163 mm)
Figure 8.6
– TB50 Dimensions with SCSI Cable
Inputs
The controller accepts analog sensor inputs which are measured and may be used as feedback
for control loops. It also accepts digital (TTL) inputs which may be used to trigger certain firmware
features.
Table 8.8
– Analog Inputs
Number of Control Loops
Options for four or eight
Number of Analog Inputs
Four-loop models: 4 analog inputs
Eight-loop models: 8 analog inputs
Input Switching
Differential, solid-state multiplexer
Input Sampling Rate
Four-loop models: 6 Hz (167ms) at 60Hz; 5Hz (200ms) at 50 Hz
Eight-loop models: 3 Hz (333ms) at 60Hz; 2.5Hz (400ms) at 50 Hz
Miliampere Inputs
0 to 20mA (3
Ω
resistance) with scaling resistors
Voltage Input Ranges Available
0 to 10V, 0 to 5V with scaling resistors
Source Impedance
For 60mV thermocouple, measurements are within specification with
up to 500Ω source resistance
For other types of analog signals, the maximum source impedance is
5000Ω
Input Range
-10 to +60mV, or 0 to 10V with scaling resistors
Resolution
0.006%, greater than 14 bits (internal)
Accuracy
0.03% of full scale (60mV) at 25 °C
0.08% of full scale (60mV) at 0 to 50 °C
Analog Over Voltage Protection
±20V referenced to digital ground.
Maximum Common Mode Voltage
5V input to input or input to analog common
Common Mode Rejection (CMR)
For inputs that do not exceed ±5V, >60dB dc to 1kHz, and 120dB at
selected line frequency.