User`s manual

PK2100
I/O Configurations s 3-11
+

V
R11R1
R5
RP5A
R2
+10 V
47 kΩ
47 kΩ
470 kΩ
V
0
g = g
0
×






1 –






1
1 +
R5
R2
+
R5
R1
.
−1












++
350
000,47
350
000,47
1
1
9962.0=
The gain for a bridge such as
would be
The change in gain for the input (V  V
0
) is given by the above formula.
If R5 is 47 kΩ and R1 and R2 are each 350 Ω, then the gain is reduced by
the factor
or about 4 parts in 1000.
Relay Outputs
The PK2100 has two relays. Each relay (Figure 3-10) is single pole,
double throw. The rated current is 3A and the rated voltage is 48V.
Optional metal-oxide varistors (MOV) may be installed on the board to
protect the contacts. When the voltage across the contact exceeds the
trigger voltage of the MOV, the MOV acts as a short circuit, preventing or
minimizing sparking and arcing.
Figure 3-10. PK2100 Relay
A
B
+24 V
NC
NO
COM