MODEL 158A 909GF197B
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NOTES:
1. IN FIGURE 1, THE TRANSMITTER IS CSA CERTIFIED FOR HAZARDOUS LOCATIONS, CLASS I, DIVISION 1, GROUPS C & D;
CLASS II, DIVISION 1, GROUPS E, F & G. THE PROBE IS INTRINSICALLY SAFE FOR CLASS I, DIVISION 1, GROUPS A, B, C &
D; CLASS II, DIVISION 1, GROUPS E, F & G.
IN FIGURE 2, THE TRANSMITTER IS CSA CERTIFIED FOR ENCLOSURE 5. THE PROBE IS INTRINSICALLY SAFE FOR
CLASS I, DIVISION 1, GROUPS A, B, C & D; CLASS II, DIVISION 1, GROUPS E, F & G.
2. R. STAHL INC., MODEL 8901/33-293/000-79 OR CSA CERTIFIED EQUIVALENT (28.1V MAX., 300 OHM MIN.) POSITIVE-
POTENTIAL SIGNAL RETURN LINE BARRIER WITH INTRINSICALLY SAFE TERMINALS 2 (GROUND) AND 3. BARRIER MUST
BE MOUNTED AND GROUNDED OUTSIDE THE HAZARDOUS AREA IN ACCORDANCE WITH THE INSTRUCTIONS PACKED
WITH BARRIER. POTENTIAL TO GROUND MUST NOT EXCEED 250V RMS (360V PEAK).
3. ROBERTSHAW MODELS 158A – (A, B) (1, 2) – (C, D) 1.
4. ROBERTSHAW MODELS 158A – (A, B) (1, 2) – (A, B) 1.
5. ROBERTSHAW MODEL 702, 728, 729, 736, 738, 739, 740 0R 741 PROBE. INSULATED PROBES ONLY MAY BE USED IN
CLASS II, GROUPS E & F AREAS.
6. 650 OHMS MAXIMUM TOTAL LOOP RESISTANCE, EXCLUDING BARRIER RESISTANCE.
7. FOR AN INTRINSICALLY SAFE INSTALLATION, ALL WIRING BETWEEN THE BARRIER AND THE TRANSMITTER MUST BE
INSTALLED IN RIGID METAL CONDUIT.
FIGURE 8 – DRAWING 907GA518
DIAGRAM FOR INTRINSICALLY SAFE INTERCONNECTIONS FOR
MODELS 158A
A, B
1, 2
A, B, C, D
1.
