Electrical Connections - Renishaw RGH22 Installation Manual

Electrical connections

Grounding and shielding
RGH22
Inner shield
Outer shield
*
Maximum extension cable length
RGH22A and B -100 m, RGH22D, X, Z, P, Q and R - 50 m, RGH22Y, S and H -20 m
IMPORTANT: The outer shield should be connected to the machine earth (Field Ground). The inner shield should be connected
to 0 V. Care should be taken to ensure that the inner and outer shields are insulated from each other. If the inner and outer shields
are connected together, this will cause a short between 0 V and earth, which could cause electrical noise issues.
Recommended signal termination
Digital outputs - RGH22D, X, Z, Y, H, P, Q, R and S
0 V
Readhead
A B Z E+
= 120 Ω 120 Ω
Cable Z
0
A B Z E-
0 V
Standard RS422A line receiver circuitry.
Capacitors recommended for improved noise immunity.
†
Only required on alarm channel E for fail safe operation.
RGH22 RGS20 installation guide
Extension cable
Customer
†
220 pF 1k
electronics
†
220 pF 1k
0 V
Customer
electronics
5 V
*
Output
signals
0 V
Analogue output - RGH22 A, B
V V V +
0 1 2
120 Ω
V V V -
0 1 2
Limit output
5 V - 25 V
R
P Q V V
p q
Select R so that maximum current does not exceed 20 mA.
Alternatively, use a relay or opto-isolator.
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